I was playing the Sims 2 (I'm too cheap to get the Sims 3, so sue me), and had heard about something you could do that was so utterly ridiculous that I had to try it out. I've only got one screenshot of it, but I think that it explains itself...
That's a waist-high wall, folks. Waist-high. Logically, one would just climb over it, right? Not Mr. Brainac here. He starved to death, the idiot. *shakes head* Oh, Sims 2, how I love you.