I manipulated my schedule into having an extra long, late lunch break with a friend so I could watch the Tiger game today and Tiger fans, as they have throughout the series in Cincy and Chicago, were LOUD starting raucous 'Let's go Tigers' chants and pretty much turning Wrigley into Comerica Park. My friend and I both thought it was awesome, but I thought it was slightly inappropriate. Let me explain.
I believe that any baseball fan is bound to different rules of etiquette based on whether the game is home or away. For me, if I go to an away game I will refrain from numerous behaviors that I partake in at Comerica Park. For example, I will not stand up and yell 'PRRRRIIIINNNNCCCCCEEEE' as Fielder strides to the plate as I would at Comerica Park, nor will l stand up for the last out of a Tiger win, and I certainly will not participate in a 'Let's Go Tigers!' chant. It's not that I didn't smile and enjoy the Wrigley series, but I have simply know how obnoxious it is as a season ticket holder who has frequently attended Tiger games in Detroit since the mid-90's. There is nothing more infuriating than a Yankee fan getting up in front of you and chanting 'DE-REK JE-TER'. My statement to people like that is always the same; there is a place for that and it is in Yankee Stadium and not Comerica Park. If you want to cheer like this is your ballpark, then go to your ballpark.
Now of course there are exceptions (mind you these are my own rules). If there is some sort of special baseball event (division clinching win, no-hitter, etc...) go nuts. If it is any divisional team, go nuts. I also realize that some people can't get back to Detroit for a game. My response would be too bad. You chose where to live and which team to root for so now you must live with the rules of baseball etiquette! Of course, I'm a bit bias because I attend Tiger games regularly. But I have HATED far too many Yankee fans, Red Sox fans, and even Indian fans from back in the day to every partake in that behavior.
Baseball is so unique because it is played everyday. Because it is played everyday, part of its joy is in the serenity of its ubiquitous presence in the summer and for the fans the ballpark can start to feel like a second home in the summer. Of course you can cheer. Scream your brains out for a big home run, a big strikeout, whatever. But I would say there are limits. But everyone is obviously free to disagree....