Registration Fees

I read this morning that Philadelphia is thinking of charging incoming prisoners to its City Jail a $35 Registration Fee.

Why is it that my daughter's Catholic Elementary school is charging me a $150 Registration Fee---and that's for someone who's attended the school for 7 years (well, 8 if you count Kindergarten).

Does it cost that much more to process a student than a prisoner?

I hate it when school 'fees' are used in this way---if it's a deposit to hold a child's place, call it a deposit, and refund it or credit it to the tuition when the child attends.