A varsity coach with a rule book situation happened just once to me.
Home team is in the 1B side dugout, I'm in "A", when the HC calls to me that the V pitcher has an illegal uniform. I hadn't noticed anything to this point (3rd inning), but looked again... "Coach, his uni is OK". Between the next at bat, as I'm walking back to "A", I see him with rulebook in hand, looking at me as he starts to walk out of the dugout. "Coach, dont come out here with that", that was enough for him to toss it onto the bench and request time, which I granted.
Now this coach is known for being ticky tac, one who always complains about alleged minor infractions, at the expense of actually coaching his team (we've all run into this type). So, he comes out and again says that F1's uni is illegal. I ask in what way, he says that F1's hat doesn't have the letter B (1st letter if the teams school name)but the rest of the team have it. I give him a stare and tell him to get back to the dugout.
After the game, walking through the V teams gate, the VC politely asked what was the issue with the HC and his F1. After telling him, he mentions that since they are a small rural school, the players have to buy their own hats, all the same 2 colors, but F1 couldnt get the "B" embroidered on in time.....
True story....