I heard on the news last week of a little league team in Beaumont, TX that is doing it, and plans to do it all season. The whole team.
I haven’t researched to see if there’s been any backlash, but I’m guessing there’s been at least some. There certainly would be if I had a child on that team or any opposing one.
Those are easy to fix, start boycotting their local sponsors. When their business falls off they will withdraw support and the teams collapse from lack of $$. Or coach gets the message real quick.