I only made it to the Arclight in Hollywood once, for a Cinerama screening of How The West Was Won a few years ago, with a couple cast members from the film (and Gregory Peck’s family) in attendance. It was pretty great!
The theater with a special place in my heart for me is at the George Eastman House in Rochester NY, a photography and film museum built in the Kodak founder’s mansion, which has a massive film archive. The theater was kind of run down (it was just majorly spruced up this summer, but I haven’t been back to see it), with a lot of charm (it’s in an early 1900s mansion…), and broken seats… but top-notch projection (and they have the equipment to project absolutely anything, even volatile nitrate film).
They play something different every night, either something from their archives or new restorations of classic films, arthouse type films not in wide release, etc. - I even saw Godzilla Final Wars there, which had only one other screening in the US, at an Asian film festival in SF. Always with a live introduction by film historians or people knowledgeable about the film’s subject matter (a couple of record shop owners introduced Repo Man), and sometimes the director or cast members.
And they have popcorn, and it’s cheap. I was a cheapskate university student when I lived in Rochester though so I usually didn’t buy it.
And I agree that a lot of films are more entertaining, and/or more meaningful, when seen with an audience. That doesn’t just apply to comedies and horror movies - I’ve even seen serious documentaries that had a bigger impact because I was with an audience. And the best are “so bad it’s good” type movies - I saw some of those at the Silent Movie Theater in Hollywood which was fun.
Not everybody necessarily cares about the “experience” aspect of moviegoing, of course… or for example they don’t appreciate how going to a run-down cheap theater could possibly add anything 
And even at theaters that draw good audiences, there can still be problems… at the George Eastman House I sat in the same broken seat every time I went, in the second row (which was only slightly too close to the relatively small screen). About 75% of the time, this lady with big hair would come running in just as the movie was starting (or a couple minutes late) and sit in the seat that she sat in every time she went… which was the one right in front of me.
Finally, these days I eat a lot of popcorn at home when watching movies on TCM, using an air popper my parents have had for 30 years or so. I use one of those olive oil mist sprayers and salt (which sticks to the oil); never been a big fan of butter on popcorn (whether movie theater “butter” or real butter)
