They're just a tech solution orchestrating (recurring) payments to your payment processors. So they don't have to do the same checks as processors. So they are only a technical single point of failure.

All they really do is handle tokenization and pci compliance. They're not an active participant in the financial process, basically just a technical proxy. Thus no risk (to them) of charge backs or anything like that, so aside from you not paying your bill, they would have little to no reason to nuke your account.