I have not read or seen any reports that beer sales are down at baseball games or similar venues. That could just mean that nobody is talking about it.....
If the park has a single-beer contract....you will arrive to find one single product as a beer option. Wouldn’t shock me if half the ball parks in the US had this type of contract.
I heard the Tampa Bay Rays are offering 2 for 1 on Bud Light on their next home stand.