First of all, it’s important to remember that theater and film are two completely different forms of media. Don’t be folled by their similarities. The question of the OP is more like “Why do I like reading novels but hate going to the opera?” than, I dunno, “Why do I like science-fiction novels but not fantasy novels?” It’s still a perfectly reasonable thing to wonder about, but don’t make the mistake of thinking that theater and film are more alike than they are.
I think film has spoiled some people for theater because they expect plays to be like movies. If you ever want to enjoy theater, you’ve just got to get that notion out of your head. Plays are not movies, you will not be able to see the same things you do in movies, and the acting style is not going to be the same as in movies. That’s just the way it is. You have to go into the theater with the right expectations, otherwise you’re bound to be disappointed – just like you’d be disappointed reading a book if you expected to hear the character’s voices.
Of course, it’s also important to remember that plenty of theatrical performances really aren’t all that good. The world is not full of truly great actors. The ones who are truly great are rarely going to be doing a show in your hometown, unless your hometown is someplace like NYC or London. A Hollywood movie may be able to put some of the finest actors in the world before you, but the best many theatrical companies can manage is the finest actors in town. I’ve seen campus theater Shakespeare and I’ve seen Shakespeare at The Globe, and they were very different experiences. If I’d never had the chance to see the latter, I might think seeing Shakespeare live was overrated and figure that you might as well watch the movie instead.
Oh, and to The Scrivener, my favorite play of all time is Rosencrantz and Guildenstern Are Dead…and it made a pretty bad movie. Not because the script was bad (it was essentially the same as the play script, after all!), or because the actors or sets or costumes or directing were bad. In fact, it may be overly harsh to say it was a “bad” movie, but it didn’t work. It simply did not work on screen the way it works on stage.
This camera effect gives the illusion of a lot of drama. Anyone ever play the Resident Evil series of video games? Notice how the camera generally looks at your character from a stationary location, then follows you as you move. This gives the illusion that something’s on the ceiling watching you as you walk around, and it’s CREEPY. You can’t do that in a play.