Most housekeeping positions at any hotel do not make less than minimum wage, but it's always been standard etiquette to tip housekeeping.At WDW, Housekeeping is not a tipped position. Only Bell Services, Valet Parking and Food and Beverage Servers are tipped positions and make less than minimum wage. Tips make up the rest of their wages. Housekeepers have negotiated a higher wage with Disney so they are not officially a tipped position.
I'm not saying that you personally must do it. I just want to make it clear to others that it is under any etiquette guideline, and generally expected, to leave a tip while staying at a hotel.
The "tipping" has nothing to do with if they make less than minimum wage.