Yeah, i think most people agree about laughtracks these days. Well, i hope cause i hate it too. But i think the pun thing is mostly just culturally translated. I think if you asked most people why, some would have a vague idea that it might be more funny but i bet the number of people that could give a plausible reason would be very small. People do it in hacky comedies so that they can place a pause and a laugh track to force the audience to laugh. A lot of humor is socially constructed and our own sense of what is funny is certainly no where near the same across the globe. I think sitcom TV culture has influenced us Americans in many ways, including how we handle puns in speech.
Most people think of it as camaraderie, like I'm nudging you into the joke with me