Well for banks your account is usually tied to a local brick-and-mortar agency, where it's definitely someone's problem if a customer comes in and refuses to leave. It's one of the reasons I'll never go with fully online banks.
The police can remove you from the building if you refuse to leave.
>It's one of the reasons I'll never go with fully online banks.
Offline banks are increasingly phased out in many places (closing branches, limiting options, strick appointment only visits, reducing stuff, etc).