I was watching 30 Rock earlier and one of the lines was something like "What do I have? A sims family that keeps getting murdered." I happened to be watching it with my mom and sister and they both looked at me like "Are you sure she said sims?" They are convinced I'm the only one who really plays it.
You might want to point out to them that the Sims is the best selling video game franchise in the history of video games, with the Sims 3 itself coming in at #7 on the list of the best selling video games of all times (Sims 1 and 2 are first and second place respectively).
Sims 3 out sold several big name titles, such as the original Half-Life, Diablo II, Guild Wars, and all 3 of the Doom games
combined. And when you look at the games that have done better (World of Warcraft, Half-Life 2, Starcraft, and Battlefield 2), 7th place is pretty darned good.