If you cannot withdraw it at will, at least it should give some interest... A withdraw limit won't really keep anyone from spending it, they will just withdaw more at once :D.
Wasn't the original concept for the bank something like you had to choose between two types of bank account, one with higher interest and higher withdraw fee (saver) and one with low/no withdraw fee and low interest (basic)? I remember I had to choose when I created my bank account, but it was bugged from the beginning, giving the same type of account no matter which you chose, and no interest at all.
There is no point in having a bank account right now in my opinion (other than the TU transfer option of course).