Since the thread started off with a comment about cell phones, perhaps the current US situation as viewed in a recent article would be of interest:

Most Americans are in cell phone jail

Providers have worked hard to lock customers into losing situations

A "customer correspondence" quoted in the article sums up much of it:

I'm currently in the middle of a two-year contract with Verizon Wireless. They just notified me that they are dramatically increasing the charges I pay for receiving each text message from 2 cents to 10 cents.

When I called to complain, they left me with a few choices, and I was unhappy with all of them. I could simply accept the increase in charges. Alternatively, I could sign up for an unlimited text messaging plan for another $5/month, but only if I renew with Verizon for another two years. Or, I could end my contract and pay an early termination fee of $175.

If I don't pay the fee and change my plan to get the best rate for text messaging, then I'm locked in with Verizon for even longer than I originally would have been had they just kept the rates the same. And since the new plan also has an early termination fee, I'll face the same problem if they decide, without my agreement, to change the plan again to suit their needs.

There's more at the link, and other tricks and gimmicks that are common.

John