I think RCCL started charging about $3.00 for room service --and I think I'm correct here -- from 1 a.m. to 5 a.m.
I do not blame them nor any other line for doing so--that's a small amount considering the waste of food they were incurring.
Kids ordering loads of food at all hours , drunks coming in at 1-2 a.m., ordering a load of food. plopping down and passing out on the bed--then the waiter has to trudge half a mile with a heavy tray of food, can't knock discreetly on the door to get someone--he / she is then faced with trying to knock loudly enough to get someone to the door and in the process awakens several people in surrounding cabins, and gets complaints for that-- or has to go somewhere to a house phone, call the people who ordered and finally carries the tray of food back to the kitchen. Don't blame the cruise lines for this-- like many things in cruising, you have to blame some of your fellow cruisers for shooting everyone in the foot by abusing a good thing.