Originally Posted by StevieTopSiders

Fun story, I once peed in the first class lav (rear had a line, I was right up there in Premium Class or w/e) and was chided by the flight attendant. I was embarrassed, so I provided feedback on the flight, saying they should specify who could use which lavatory (which is implied, but was never explicitly stated (and I didn't know at the time)). I got an email from the VP of something asking for more details, and now they make an announcement to the effect of "Please use the lavatory in your class."

So yes, they do read stuff, which is cool.