[germanier]

The federal antitrust commission intervened after banks filed a lawsuit to stop Sofort from using their websites. The passages of their TOS that forbid using such services are most likely void as they obstruct a free market of payment providers (as seen by the federal antitrust commission).

Personally, I avoid that service but it has the blessing of government agencies from operating that way.

Some banks (e.g. DKB) now started to cooperate with Sofort instead and the German banks will start a similar service themselves this year.