Re: What about pre-payment?
"Sorry, this site has been suspended because they didn't have enough credit in their account."
Except they don't have to put up a message of that kind. All they have to do is report the unavailability, not the reason why.
Even if pre-payment isn't desirable it would be reasonable enough to put a cap on things, trigger an authorisation request from the payer to keep the service running and incurring costs. That could be opt-out for those who want to take the risk.
Customers are going to demand things like that if Amazon stops refunding money for carelessness and mistakes.