That employee you want me to sympathize with is usually working for a scammer like "Heather From Account Services" or "Microsoft Technical Support" or "The IRS", or at best for "Maybe they really are selling solar panels for your roof but they didn't check the Do Not Call list or their own Don't Call Me Back list or even figure out if they're calling a home or business", so if they aren't thieves themselves they're working for shoddy businesses that waste their time and the time of the people they're calling, so they're probably going to do just as bad a job of providing services to anybody they sucker into buying.
And if you marked them as interested just so they get more calls, you're an asshole who deserved whatever they said to you.
I've occasionally gotten calls from surveys that probably were real Gallup polls, but unfortunately for them I've got no interest in telling them my age or income level, even though I'd happily tell them that I'm planning to vote "other" rather than Democrat or Republican, no, I'm not undecided, yes, I think Obama's done a terrible job but any of the Republicans would be even worse (or, if it's a push poll for one of the candidates or parties or political fund-raising groups, that their questions are so hopeless that there's no way to answer their "Politician X, Threat Or Menace?".)