Yeah, in older games. But there are literally about a thousand sim filters choosing who does what, now. Every one of them would have to be edited to change the choices. I know, because over time I've done about 400 of them myself to get rid of random sims (I hate them, too). Each neighborhood has a walkby director that will direct something like at 8am 6-8 sims will appear; sims going to school, work, jogging, an ambient mailman, etc. Then at 10am there will be 6-8 or something more. It's all very directed, and they'd either have to start all over or change all of it. You do notice though that there are a lot of the same sims doing things like manning the stalls or bartending. That's because when the game generates them, it tags them with those jobs. But for some reason it makes more. And more.
