I've seen a number of news segments about this. First, I want to say, I agree with using humor and "messing with" these people. Anything that wastes their time is fine with me. There are websites where people post these kinds of pranks, which can be quite entertaining.

Here's why they harass you, even when you tell them you don't have money: It's their job to do whatever they can (within the law) to get you to pay, even if it's small payments at a time. They get paid for getting as many people as they can. Therefore, they do what they can to get you to pay.

Now, here's something you may not know: Many credit card companies will tell you they don't encourage belligerent and foul language and threats. But the employees that make these calls aren't necessarily "corrected" if there are no complaints to the company itself, and these threats often get people to pay, because many people don't know they're illegal. And the companies do get sued, but they don't care, because they make far more money with the way they do things, despite the lawsuits. I saw some debt collectors on 20/20, I think it was, saying this a few months ago.

Our society also screws us when we avoid going into debt because if you don't have credit--like me--it makes it a lot harder to buy a house, car, or other major purchases. You have to literally put yourself in debt (I mean, you're in debt until you pay the monthly bill, at least for the weeks before you receive the bill) to build up a credit history and show you're worthy of being trusted to make payments.