My WAG (Wild A$$ Guess) is X intentionally does this to save money as they know the last night is the least visited night. Many do not want to get dressed up, go to a 90mins-2 hour dinner or potentially get anxiety about not yet being packed. Lastly, its well-known that many staff members including the waitstaff could fish for tips on the last night and some want to avoid that. In my experience they're not bad, they can be a bit more friendly and try to have longer conversations but it isn't bad; its nothing compared to some of the bad porters I've experienced...Example of one of the worst porters, something like: "We a team baby <puts out fist to fist bump>...You take good care of me and I'll take good care of your bags...Teamwork makes the dream work, baby!"