Of course they are. Just like the telco's and long distance charges. The lines where long paid for but they just keep say that to many people are making LD calls so to help increase the number we need more money. All the while they don't actually increase capacity and just pocket the money.
How we solve this I don't know. The only thing I can think of is to move to the ISP's that aren't gouging as much as the next guy. I know that's hard. I also live in a small town and have very limited choices of ISP's.
Here's one way to try and save your self some money. Buy shares in the ISP (if public). Just like the banks. Try and get some shares so you to can get in on the profits. Yes again easier said then done. I don't have solutions for everything and everyone just ideas, and not always good ones.