They can't go to every single theater and test out the film. There isn't a list of theaters with bad sound. It just is what it is. Similar to back when there was film projection, you could go see a film and it look like crap because the print is scratched and the projectionist is a new kid who doesn't know what he's doing. Like I said, it just is what it is. That said, I know for a fact that most good directors would do just that (check every single theater) if it was humanly possible. PTA watched Magnolia in every theater in the L.A. area and gave the projectionists directions. Chris Nolan apparently did a similar thing with Inception. Scorsese hassled a high school kid working as a projectionist in New York because he walked in on Raging Bull and it looked like ****. Scorsese has complained about the sound a lot recently.
I can't speak for everyone, but the systems at my local theater (and its chain which I won't name) are 25 years old exactly. As far as theaters dying, for the most part, movie theaters are doing worse and worse business, partially due to things like Netflix, VOD, Redbox ect and partially due to the rise of quality in TV. There are many factors, no one knows for sure. Speilberg and Lucas think they'll be gone in ten years. I think that's going a bit chicken little on the situation, but it's definitely at a crossroads, to say the least.