There's the fallacy in your thinking. "Lion's share". What makes you think pro pool deserves ANY share of that money?
Neither is old school, apparently. It's still available, yet nobody's taking that route.
It's a rung in the ladder, just like little league and Pop Warner. It's near the bottom, just like them. Each rung in the ladder gets smaller as you go up. Advancing up the ladder requires increasing skill and a lot of sacrifice. As the skill increases, the rule sets you play by change appropriately. Think tee ball to MLB. The ball is set on a tee for you because the skill to throw a pitch or to hit a moving ball hasn't yet been developed. As players advance, the tees are removed and it becomes coach-pitch and eventually player-pitch. The playing field is smaller. Throughout that stage there are no winners or losers - many don't even keep score. Bastardized rules. The difference is tee ball and little league players are not expected to develop themselves into pros. There's pony league, colt league, high school, college, and minor leagues (A, AA, AAA), all financed in part by the pros, not little leagues. Rungs in the ladder that are fully developed, each getting smaller and harder as players progress. Those rungs don't exist or are severely broken in the sport of pool, but it's not the fault of the leagues, the bottom rungs on the ladder. They do their jobs, bring people in.
In my business 30% retention year-to-year is considered good. That means 30% of our customers every year are people who did not play the year before, meaning we gotta find that many customers just to stay the size we were last year. Why do the 30% leave? Most of it is out of the bottom skills, as people tried it out, decided it wasn't for them, and left. That's expected. It's also expected that people's life conditions change. They move, change jobs, have children, etc. There are also those who "develop out" of the system - that's where your "return on investment" comes in. They see the huge void between leagues and the pros, and decide the investment in time and money isn't worth their returns. Again, not the fault of leagues, if anything it's more the fault of professional pool. All of those successful leagues started out in the red. Players and coaches had "real" jobs, both during the season and in the offseason. I'm talking generations of players and coaches, not one or two. They sacrificed for decades, spent their entire careers to build the popularity of the sport, playing just for love of the game - the pros. Pool will not grow overnight. It will take generations of pros who are willing to stick at it and make those sacrifices.
As for operators in upstate New York who hold locations hostage, cut them out, etc., I don't know upstate New York, so I can't speak to that. I don't have the kind of market where I can move teams and tournaments willy-nilly. Maybe they don't either - I don't know. All I can say is that if it's not for a good reason (mistreatment of players, etc.) I don't think that's good business.