I really don't like the way these new roled jobs (cashier, tattooist, etc) work. EA stuffed up on this. These "roled jobs" should have been assigned to NPCs, like the stylists, baristas, cashiers, etc in TS2. In TS2, if a playable sim owned a business then they could employ playables in these positions, but the positions were filled by NPCs if the business was not owned.
As it is, these roled jobs are neither fish nor fowl, the jobs are neither completely playable nor NPC. If I can't put a playable sim into the cashier job then the game shouldn't be assigning it to playables.
I like to play entire neighbourhoods, not restrict myself to just one household, switching as the whim takes me. In empty neighbourhoods I've started since installing Ambitions, I'm seeing new sims created to fill these roled jobs. When I switch to a household with a sim in a roled job, they instantly become unemployed and I get more sims created to fill the now vacant positions (apart from the sylists who are instantly promoted to level 8 without any effort).
I haven't dared play my main hood since installing Ambitions, since I have stocked it entirely with red, blue, and green sims, and the game-created sims that fill the jobs are from the standard skin-swatch.