My kids have used my rewards number for stays for rooms that I did not occupy. When I do this, I put both my name and their name on the reservation. I call the hotel and have them note that my son will be checking in first. They do this to take advantage of the concierge access, the higher MRP bonus (that I move to their accounts) and the hotel discounts I have access to. I do this only when they ask me to do it. I have also used MR points for room that they stayed in without me being there. I usually offer this. The sum total of times I did something for a room I did not occupy is maybe 15 times.
Is this against the rules? Yes. I do remind them as with any rule, if you break it and there are consequences, you suffer them. If they use my points based on my offering, if anything happened, I would be responsible for whatever they had to pay for the room.
Am I not advocating for anyone else to do this. I would only do this for my family and I am comfortable with it. Never had an issue but again, if there was, there is no one else to blame.