Your job reflects how Aryan are you considered, and so do your "luxuries", for example less Aryan factory worker shares a normal-sized house with his wife, sleeps on an average bed, and is given only oats for breakfast, with two eggs given to him as a reward by the SS for his help seen as something truly luxurious, while a more Aryan SS soldier lives in a small room, has nearly no personal belongings, to not spoil his Aryan character, but gets good food to make a good, healthy soldier. Either way, the main idea of all this is to create a perfect society, where luxuries and material possessions mean nothing, and everybody lives their lives as a happy little strong Aryans (as this system is designed to eradicate all weak individuals).
Material luxuries are to be tightly restricted, ideological flexibility is not tolerated under any circumstances, occupied people of lesser races are never given leniency, and everyone must constantly be on war footing until the other races of the world are defeated. The SS acts as an ideological vanguard, a tool of both indoctrination and enforcement to mold the next generation of Nazi fanatics. Himmler believes that the regime he's imposing on them is as close to the ideal Aryan lifestyle as can be, and after a few generations of having to "fake it til you make it," this lifestyle would feel natural to the Aryan people and they'll partake in it willingly.
Of course, in reality, all of this only created an awful hellhole that is objectively worse even than the 1984 Ingsoc system.