Every time my sims have anyone over EVERYONE starts stealing everything— my couch was stolen four times, my coffee tables, kitchen counters. I went into CAS to remove the klepto trait but the sims didn't even have it, or the sticky fingers aspiration, and then the sims kept stealing my stuff. I think this is from the robber update or maybe businesses and hobbies, not sure.
I use mccc and that's it, I even tried disabled it and it still happened.