I did it for my sister-in-law. When she came to visit us during Thanksgiving, all the guest rooms were full of visiting family members from my side. I just book a room under my name, pay for it, and gave her the key. The front desk doesn't need to know that I am not staying in the room. Although it would have seem very suspicious that I got a room 2 miles from my home address if someone decided to check into it. She has no problem using the breakfast vouchers at breakfast even though they have my name on it.

You do have to trust the person staying in the room. If she decided to order tons of room services and pay-per-views, it would have came out from my credit card.