The only real benefit is the rankings and points. Some people really care a lot about the points while others don't.
I've been playing in leagues and tournaments since 2012 and most have been IFPA sanctioned. I'm not point crazy but it is nice to have it. I just like having a reason to play pinball, hanging out with friends, and i enjoy competitive play since it really changes strategy.
Good luck growing the league and if I'm in Kent I'll stop by and drop in some quarters.
I'm not the biggest fan of the dollar thing but hell DI or the newest stern cost me a buck a game and I like competitive pinball.