This causes unexpected problems. Depending on how it's implemented (and in a "fair" way or not), the housekeeping / cleaning staff object to this sometimes on grounds that they're being deprived of hours of work. So in fact I have experienced at some hotels (off the books of course), the housekeeping staff asking you to not accept the points-for-no-housekeeping option.
It's kind of like the situation I heard a where a new "green"/eco building was being built on campus. The plumbers union objected to the decreased amount of copper pipes being installed and the associated lesser amount of labor they were employed for (due to water saving fixtures, no flush urinals, etc) so the university had to give in to allow all the usual pipes to be installed even if they weren't to be used. (or maybe it was in union anticipation of the eco-solution failing some day and needing to fall back on the traditional plumbing setup).
Conflicting incentives...