[kovidgoyal]

And as someone who uses PayPal to collect money, all the horrors of PayPal freezing your account can be avoided by simply setting it up to transfer money to your bank account automatically as it is received. So if PayPal does happen to lock your account, all you lose is at most one weekend's income (since transfers do not happen on weekends). Given that as you rightly point out, PayPal is not a bank, why would you trust it to hold significant quantities of your money in any case?

As for not being able to contact PayPal, I have always been able to contact them via their phone support, not just that, on several occasions, they have contacted me, to, for instance, change my account settings to decrease the processing fees, I have to pay.

And they have no competitors that can match their global coverage. So PayPal is pretty much the only choice here (although calibre also accepts payments via Bitcoin)