Streets are one of the only places that all bank robbers go after a robbery, just to get out of the bank. This is why we can't have streets... ?!? Jokes aside

Streets are one of the only places that all bank robbers go after a robbery, just to get out of the bank. This is why we can't have streets... ?!? Jokes aside, you just provided a very good example of the prison mindset: Instead of trying to understand the "problem" of students going too often to the bathroom, the default choice is to make the behavior prohibited.