First, get your hands on the book by Bruce Weber "As They See 'Em". He writes a bit about what you're saying happened with that travel team. Umpires used to do that very thing but TV, their ratings system, etc. has forced them to become more consistent. Hey, I'm not saying it doesn't happen but I would doubt it happens very much because it affects their ratings.
Look, I did a varsity game 2 days ago where the team was up 18-1 in the 3rd inning. Did I open up the strike zone on the team that was up? **** right. Nobody wants to prolong a game like that.
However, the pros have a show to put on. They must be very careful of the sort of thing that I did. Too many people pay a lot of $$$$ to watch them play.
Hope this helps. Wish I had seen that game you saw. Did the media comment on it?