A lot of merchants (e.g. Amazon) don't use PayPal because is isn't a real bank, and so isn't beholden by laws associated with banks. The terms of service state

A lot of merchants (e.g. Amazon) don't use PayPal because is isn't a real bank, and so isn't beholden by laws associated with banks. The terms of service state that you cannot seek any legal recourse from them should your account be shut down. How could this affect a VPS provider? Say a customer hosts a porn site, or a gun-selling site, or something else PayPal disagrees with. PayPal shuts the merchant's account down for it. Now the merchant's funds are frozen for an indeterminate amount of time till the issue can be resolved, if at all, and there's nothing they can do about it short of appealing to PayPal.