At the luxury level the camp is small, the location is private, and almost everything is included: your own vehicle and guide, all meals, all drinks including wine and spirits, laundry, park fees and often scheduled flights between camps.
Rooms are suites. Guiding steps up markedly — the best guides in Tanzania work at this level, many of them silver-level certified with a decade or more in the same ecosystem, and the difference on a game drive is enormous.
Because many luxury camps sit in private concessions rather than the national park, they can do things the park forbids: night drives, walking safaris, and off-road driving to reach a sighting. That access, more than the bathrooms, is what people are actually paying for.