This exact same thing happened to me! The Romance Festival was there the entire week and GeekCon was practically unusable. The only way I found to fix it was to stay til the end of the next Romance Festival (which for some reason another one spawned so there was 2 of everything) and then everything should disappear. Luckily I was playing in one of the apartments in that district at the time so it didn't matter so much having to wait til the end. But it sure is annoying having to wait out til 2am with my sims each time they visit that festival! I wish this bug would get fixed.