Your experiences arent all that exist and they only address marathon sessions.
I went looking for my running partner once years ago. His wife and two small children were sitting at home with no food when I stopped there first. He was down the road playing pool, had been for three days. When I got there an old man that couldn't begin to play with my partner when he was straight had caught him in a match after my partner had busted a handful of other people. When I got there B was down to about $150 and fixing to lose that. He couldn't make a ball in a #3 washtub but he was too fried to know it. Knowing the old man I am sure he had just touched base a few times or told the counterman to give him a call when the time was right. He let B win a nice stack the hard way then plucked him like a chicken!
Different rules apply to real friends than pool hall ethics and I pretty much drug my friend out by the ear with grocery money left.
Most people aren't playing nearly as well as they think they are on chemicals and nobody has to be off their game very much for a decent shortstop to take them. In a long match I take frequent bathroom breaks myself, to wash my face and hands.
Some others took a bathroom break and were ready to set the world on fire, except their shots were almost there. Then they did play pretty good for awhile, then they went to crap for awhile before they realized it was time for another bathroom break. They were monsters maybe 1/4 of the time and thought they were monsters 3/4 of the time.
I wasn't a monster on the natch but then again I never thought I was. I called my style of pool chopping wood. I loved hitting balls, still do. I didn't have to make a fortune, I just wanted to turn a decent profit. I usually did have a pretty fair bankroll but it didn't matter a whole lot. A chemical player generally went with a little tune-up to start and I got some of their cash early while they were flying high. Then when they got strong for awhile they were just getting their cash back. When they started losing again it was time to go back to the bathroom and the cycle repeated.
Hu