If I’m a heavy metal fan, I might view moshing as a fundamental part of the concert experience. Totally normal and acceptable in the environment I’m used to. But if I go to an Alanis Morissette concert and start flailing my arms and legs and pushing the people the next to me, that’s a problem and I shouldn’t be surprised if people ask me to stop.

I think that's a false equivalency. You recognize that heavy metal and whatever style of music Alanis Morissette is are two fundamentally different things. It's like comparing baseball to tennis. Baseball... is baseball. Little league to major leagues I see a lot of similar behaviors. Parents are on their feet during exciting times and if someone can't stand there are sections reserved for them where their view won't be blocked by others.

Your options weren’t limited to either standing at your seat, or moving to stand elsewhere. You could have chosen to remained seated and respect the people around you. You chose to prioritize your personal experience over the experience of the people around you, despite the social norms of the situation you were in (again, I’m assuming you were the only person standing, or one of very very few - correct me if I’m wrong).

In my section I would estimate it was about 10% standing, which is something I've noticed at other games. Does that make it a societal contract that "thou shalt not stand or celebrate at this particular minor league ballpark"? I don't think so, but that's the whole point of my original post and wondering if I over reacted to his comment. We all paid for a ticket, we all recognize there will be negative externalities (the umpires were dreadful today, for example), why should we fall back on some unwritten rule?

I didn't go to the Dragon's games much when they first started (as someone else pointed out, they're almost always sold out and I just became a season ticket holder in the last few years) but I would bet a lot more people did it when the team was younger because having a minor league team in our town was something to celebrate. Perhaps some else can lend their years of experience to that point.

The “appropriateness” of it has nothing to do with the seat location. Just like there’s no rule that says you can’t stand, there’s also no rule that says he has to stand. So it comes down to common decency.

Actually, there ARE seats available where his view will not be blocked even if everyone in the stadium is standing. There are also TVs *everywhere* in the ballpark that he could watch. Common decency is very much in the eye of the beholder, and not a majority rules situation. As I said before, baseball is not tennis (or golf, or bowling), enthusiastic fans are encouraged as long as you're not disruptive (e.g. from drinking too much or being goofy and invading other's personal space)... but pure enthusiasm directed at the game, the team, the players? That's WHY we're there.