I am not getting stones. I am getting sludge. It doesn't turn into a stone until you leave it in there for 75 years to petrify. If you only leave it in for 49 years, it only turns into hard rubber balls. Call them whatever you want. But they hurt and if you don't get them out, eventually your gall bladder will burst and you will get gangrene, is my unofficial unscientific understanding. And they are extremely painful. And you cannot eat a french fry without getting really bad indigestion.
The reason some people don't get them and other people do is because of genetics.