The readings said that laugh tracks are there to make insecure know when it is alright to laugh. I think everyone has been watching a movie with someone who laughs at the parts that aren't meant to be funny. If you take the laugh tracks out I think the majority of people would sill know when the movie or TV show is trying to be funny. If the laugh tracks were replaced with something like dramatic music though it would kind of make something maybe a little more depressing like this clip from Two and a Half Men.
I personally don’t have a problem with laugh tracks. When I watched this clip I was laughing because it felt like it was trying to be sad.