I might shed some light on this, I set up databases for hotel food services. This is not always the case, but the following is what most likely happens. If there is a delivery charge (usually a per trip charge which is very common at resorts and nickle and dimeing 4 and 5 stars) that goes to the house. The service charge then goes to the room service staff (Room service normally pools tips and may have to tip out a bartender as well). If there is not a delivery charge, but just a service charge, it may be that the house takes a percentage of the tip (a common one is 18% with 15% going to the server and 3% to the house). Their is no hard and fast rule, but always read the guest check closely.