When the album came out, I heard a radio interview with Waters where he explained the thought process of the album.
The mother / school part was from a friend who kept complaining to Waters about his over-bearing mother.
The hotel / being sick / concert thing was when he was on a prior tour (animals or Wish you were here: don't remember), and he got really sick.
A doctor gave him a shot so he could get through that evening's show, but the shot made it worse.
He said that concert had the feeling of a Nurenburg rally, and he could tell the crowd to do something,,, anything,, and they would.
He talked about how there was one kid in the front row, and Waters gave him the finger motion to come closer, and when the kid did, Waters spit on him.
It was strange listening to it.
BTW,
Without anyone doing a google search, or getting the album out,, can anyone answer who played the groupie in the hotel room?
At the time, I thought it strange to hear it was her, given the kind of music she was putting out at the time.
"Wanna take a bath?"
Jay