Abuse. Lots of it. Insult their intelligence, parentage, choice of job... Anything you can think of. Be as unpleasant as possible.
Do you really believe that abusing a phone monkey is going to do anything other than make you both tense and angry?
I've been on both sides of the phone, and abuse means nothing to these companies. You are just taking your frustration out on a minimum wage worker trying to make a living (probably while looking for better work). You may indeed succeed in making that one individual quit his job, but what have you gained in the process? An ulcer? Believe me, there are 10 people to take the place of any single employee who quits.
When I was making calls, I was told that I could NOT hang-up until I'd been told at-least three times that they were not interested. They enforced this rule, and others, by randomly listening in on calls all day long. And if they have had trouble with a sales person in the past, they pay particular attention to him. Too many violations of the rules and you were out.
Abuse does not get you taken off of call registries. Only a handful things will ever get you off of those lists (in order of effectiveness):
1) Say, "No thanks", and hang up.*
2) Screening your calls. (IE, answering machine or a "secret" voice-mail box / code to ring an "extension". They are told NOT to leave messages.)**
3) Add your phone number(s) to government "Do not call" lists. (What's nice about doing this is that violators can be fined or even sued, though YMMV depending where you are.)***
4) Saying, "Remove my number from your list", or "Put me on the do-not-call list". (Won't always work because this is voluntary, but it might.)
5) Not answering any call that has no caller-id, in addition to those that ID themselves as sales calls.
6) Whistling your friends, family and business associates while blacklisting known "spammers". Works even better on the phone than with email. Almost all cell-phones can do this, and all VOIP phone services I know of can do this.
7) Never buying anything over the phone. (Though requires a history, and takes a while to establish.)
I tell you that eventually your number will start coming off of the lists if you just follow the first three of the suggestions I give above. Especially about screening calls. They mark down all kinds of statistics about each number they call: No Answer, Voice Mail, Hung Up, Busy, Call Back, Sale, etc. But one statistic they don't record is if the person that answers the phone is nasty. They don't care. If you are nice and buy, that's great. If you are nasty, but get badgered into buying anyway, that's great too! A sale is a sale.
*When I was still taking business calls on my personal phone, I listened just long enough to establish that it was a sales call, then said, "Yeah, no thanks", and hung up. In fact, probably the "Yeah" was the only clear word, as the phone was already on it's way to the cradle when I spoke.
*Many people say they are uncomfortable doing this, as it is rude. Let me tell you as an ex salesman, it is not rude. I'll tell you what IS rude though. Wasting the salesperson's time by acting as if you might buy it. I find it curious how some people would rather go ALL-OUT HOG-WILD with rudeness with name-calling and cursing at the salesperson, rather than just saying, "No thanks", and hanging up. Really, hanging up is the nicest thing you can do for them, and yourself. And I recommend saying "No thanks" not just to be polite, but to prevent them from calling right back thinking you got cut off.
In fact, don't let them finish their spiel (yes, their whole speech is scripted out for them), or wait for an opening to speak. The whole thing is designed to NOT give you any place to politely opt-out. Interrupt them, saying "No thank-you", and hang-up. Don't wait for them to pause for breath, talk over them, then hang up.
Fun fact: Neither the company, nor the salesperson, want's to spend any more time with you than necessary. Why?
The Company: Each call costs them money, the longer the call, the more expensive it is. If there is no sale at the end of it, that money is not recouped.
The Sales Person: If there is a commission, he makes less money if he wastes his time arguing with people who won't buy. If there is not a commission, his stats are still followed and less sales could mean being fired, wile more sales could mean a bonus of some kind.
My theory is that they have a computer form in front of them when they call, and somewhere on that form is a little checkbox for "difficult" people.
They do not. I worked in the industry. Why do you think the company cares how you treat it's salespeople? All they care about is profit. If the salesperson feels like shit, they don't care, just as long as he can stay on the line long enough to sell you.
I hope that means they won't call me. It does seem to have reduced the number of calls I get.
My theory is that's wishful thinking on your part.
I have another theory: That you really don't care about them calling, what you care about is having to deal with them (wasting your time), and possibly keeping your line busy.
So, how's this sound? They call all the time, but never get to speak to you, so you never get bothered, AND the people who you WANT calling can still get through.
How's that sound? Good? Acceptable?
**If so then, if you can, SCREEN YOUR CALLS. And say in the outgoing message that you ARE screening your calls, and that the ONLY way to speak to you is for them to state their business, and IF you want to speak to them you will pick up. And if they try bury you under multiple calls, you'll just turn off the ringer.
Remember this MUST be done in the first few seconds of the message because phone-salespeople are TOLD to simply hang-up when they get a machine, so you have to get out your conditions before they realize that you're voice is just a recording.
This method works, I know, I used it for years, and it stopped 100% of sales calls from bothering me, though honestly I couldn't even guess how many sales-calls came to my number. It meant that occasionally I turned off the ringer on my phone for a few hours, but that was fine with me.
Right now I am using a combination of three phone numbers, one of them a VOIP number, all of which eventually come to my cell. I now screen calls via the caller ID / phone number. If there is no ID, and they leave a message, I listen to it first to decide if I know them. Sometimes I'll check the number online to see if there is a name associated with it. If I don't know them, and / or don't want to know them, I block the number. Very simple. The same goes for text messages.
This system is less than two years old and I haven't received an unwelcome call in months, and I haven't got a sales text from anyone but my carrier and those I've whitelisted, for at least a month in a half. And before that it was only about 1 per month.
But most importantly, remember, your telephone is not welded onto the side of your head. Any call that you listen to, you are doing VOLUNTARILY! No one is holding a gun to your head, and in reality the sales person CANNOT force you to listen. No matter how trapped you FEEL, YOU ARE THE ONE IN A POSITION OF POWER! The sales person CANNOT hang up until certain conditions are met. YOU, on the other hand, CAN HANG UP ANYTIME you feel like it! So, exercise your power, and hang up. Just add the "No thanks", so they wouldn't think you got disconnected and call back.