If you have had they tick a box saying that they 'agree', then it implies they have read them. I personally think it would be a waste of time.
The TOS is there to protect the host from abusers, and you can leverage the rules whether or not they have read them.
The more obstacles you place in a users way, the fewer conversions you will get.
After all, the only way you can check they have actually read them would be to test them, let's see what that would do to our conversions.