Why do apartment complex call them non-refundable deposits?

Come on, who are they kidding? Its not a non-refundable deposit, its a fee.|||Slight difference. If it's a fee, then if the damage exceeds the fee the landlord eats the excess cost. If it's a non-refundable deposit and the damage exceeds the deposit, the tenant is liable.|||In my state that is an illegal clause and is not enforceable.