The main issue isn't firing a customer (although it's bad), but locking up their money. It's not like they say "hey, we want to stop doing business with you, please transfer all your money to some other bank within a week or take out your money at the nearest branch", or do they?
Locking up the money is basically theft, but I'm sure the law and regulations say otherwise.
Locking up the money is basically theft, but I'm sure the law and regulations say otherwise.