For the same reason in any other kind of industry, when things don't work they get refunded, and when things go wrong people get sued.
Software shouldn't be a special snowflake in that regard, and because it currently is, that is what allows business to disregad quality and good software development practices.
Even 1 euro shops and street food joints have a minimal set of quality standards they must adhere to, or get closed down when not.
What possible good could ever come from involving the force of the state in something a trivial and banal as a todo list app?