Your a whiner bill. You already stated the lease has provisions that allow the management to change rules not specified in the lease. This is one of those changes. Quit trying to make a big deal out of nothing.

Of course your option is to not pay the deposit and be denied the hang tag and the key. That way you can camp out in your parking spaces because, as you stated, the use of the spaces is in your lease so they can't take that away from you.