They didn’t kick them out for “doing just that” they kicked them out for being rude and lowering the value of the restaurant for other customers.
Hey you finally said something right. Yes, restaurants exist to make money. And when you have customers that not only eat more than they spend but ALSO engage in behavior which discourages other customers these guys are inhibiting your ability to make money. So out they go.
But then you go wrong. The generally accepted semantics of “all you can eat” include “within reason, and without inhibiting other patrons ability to do the same”. 5 bowls a visit really isn’t within reason, and regularly emptying serving trays before other patrons get a chance to sample from them inhibits other patrons.
No both you and the restaurant get to decide. Because, as you said, they exist to make money, and if leaving the decision all up to you costs them money we’re now going against the very reason the place exists.
It IS society, it IS a social contract. In a society we understand that businesses exist to make money and if our patronage costs them money they can decide they don’t want it anymore. That’s part of the social contract of living in a capitalist society, the knowledge that all these business deals are voluntary in BOTH directions.
They WERE being generally disruptive. Read the article. It wasn’t just about them eating too much, they also felt the need to race other patrons to new food and take it all before anybody else got some. They broke social contracts, both with the restaurant AND with other patrons. So now they’re banned, that’s how society deals with people that aren’t potty trained, we kick them out.
As for the treacly 'social contract' crap, keep it. We used to just be considerate of others and have manners.
Most of the weasels who push 'duty to society' are just trying to get their foot in the door to shaft someone.