While this may be technically true, it is almost impossible to enforce. All you have to do is have him call and add your name as the second guest. When you check-in, just say that you got there before your friend. They will ask for a credit card to put down and then give you a key. Do express checkout when you leave and you won't even have to physically return the key.
Hotels churn through hundreds of guest each day and are busy as hell so they won't be keeping tabs on your specific case. I've done this at Vegas and numerous other hotels around the country countless times without issue. Just be nice, don't stand out, and it won't be an issue. Worst case, it's not something that an Andrew Jackson handshake can't solve.