What negative interactions are there?

Thanks @Stormkeep - I think you are right about the relations. When I tested for my project, all relations were neutral, they all did normal stuff and acted rather friendly. The negative actions did not take off when all relations were very red either, but it helped a little. Raising a sim by praise negative actions might be the best bet, but still I'm quite disappointed with how little evil or mean sims differ from the pack. They might do their "muha" animation and laugh, or they might shout the forbidden words, but they don't really harm a soul. Understanding TS4 is not supposed to be violent, but they could at least rise their fist or frown at other sims, threatening them.