I would tell Girardi to shove it. He should be more concerned with how they play on the field instead of how they look. Gee, have people forgotten that the 1997 and 2003 teams had players with beards. Anybody forget that Jim Leyland had a bushy mustache?
What would Girardi have done if he was on the '72 As? Raised hell about his teammates becoming hairy?
This what would have happened if I was a Marlin (I personally have a long ponytail and a beard). I would not shave. I would not cut. I'd let Girardi give me crap. I'd take out my checkbook and say "how much?" If he went ahead and benched/suspended me, I'd say fine and publically demand a trade, more so the better if I were a 10/5 man. After that happened, if the team I was now with played the Marlins, I'd take pre-game without a cap and ponytail out, my hair flying in front of Skinhead Joe (hey, maybe that's a reason why he's so anal-retentive).
Don't worry. Girardi won't be with the Marlins for long. Afer Torre gets canned when the Yankees flop in the post-season again, Steinbrenner'll make a deal with the Marlins to get Girardi as Torre's replacement...