Feel free to google around for any number of problems with PayPal as a company, both general screwing-their-own-users garden variety stuff and larger ethically more relevant issues.

Or, as an example, try moving or receiving and unusually (for your typical use of your PayPal account) amount of money through their systems. It's like playing Russian Roulette, s/bullet/frozen paypal account and assets/

And let's just hope you never get an itching to support a cause like Wikileaks, because you certainly won't be able to through Paypal (speaking of, last I checked Paypal never did release the many thousands worth of funds that Wikileaks had in their Paypal account when they froze it on a whim).

Edit: and yes, I happen to use PayPal myself, so to a minor extent I am a hypocrite, but the unfortunate reality is that in many cases they are the only option. I also have a VISA credit card, and they as well as most any credit card processor are guilty of things similar to PayPal. But that's part of the point, about "it's for those who don't care". If enough people did care about the issues at hand and avoided using those things as much as possible on principle, we wouldn't have this situation where the majority of the options are somehow problematic.