IF I recall correctly, at some of the larger events, like the Junior Olympics, and, maybe, the Flordia or Georgia PG events, retired professional baseball umpires are used.
I recall some games being called by an older ump (70's might have been 80's)in the Tucson heat. He was clearly having a lot of fun with the boys including my catcher son.
They were getting those seven inning games finished in and hour and half.
After the last game, the entire team circled up around that ump and had their picture made.
You might have seen a glimpse of a thinning talent pool and witnessed some great umpires impact on the game.