Moderator: Asiana & Qantas Frequent Flyer
Join Date: Dec 2006
Location: STR/SYD/SMF
Programs: QF Lifetime SG, LH HON, OZ Lifetime Diamond +, HH Diamond, Marriott Lifetime Platinum
Posts: 14,377
You have answered your own question. There is not much service which is covered by the fee. And technically there shouldn't be a a need for tipping when service is billed separately.
It is just one way of the hotel to raise more money. At least it is very transparent when you make a booking on the website.