That's pretty valid. You want there to be accountability and barriers to entry. If people wanted to do something illegal or harmful over the service, you need an easy way to track people down. If people who are getting banned want to get in, finding a new credit card each time is a lot harder than just picking up a 2 month trial. And yeah, if you didn't have a credit card associated with the account, everyone would just be inputting those trials in six times a year and nobody would pay for the service. There's been a few services that don't use cards, but I just don't see it as practical.
