Perhaps you are right Borg, I don't live in Germany, I meant in the USA.
I am not sure why anyone would allow paypal to auto-debit their account in the event they are short. Assuming they are using paypal to make a transaction, it would be smarter to take the 2 or so minutes to move money manually from your bank to paypal. I wouldn't allow any outside party the option to auto-debit anything from my account. They ask all the time but I flat out refuse. Better safe than sorry.
Especially your main account, if you have more than one. I just don't get the logic of taking on that kind of risk. They ask to do it for the electric Bill, when I used to have a car payment, cable and internet bill, but I refuse. I'd rather get the bill and pay it, and get a paper receipt. Too much can go wrong with the world of online banking.
Sorry for butting into this issue I will see my way out.