When bad ideas are considered by bad decision makers, bad things happen. I can't imagine looking into the head of the decision maker who thinks this is a good idea.
This small-time league/circuit is nothing without the good will of the community it serves and the people who buy tickets, which are almost exclusively families with children. Families with children don't always make the best decisions about family entertainment, but it is a sure bet that spending entertainment dollars celebrating organized atheism will not go over well.
I'll bet you'll have people avoid the game, and many of those who show up unaware in advance that this is happening will walk out the gate.