Quick nit-pick, and only because I've been told it's very offensive to many Japanese-Americans, but "Japophile" (It's Japanophile) might not be the best way to phrase it. I don't get the sense you're trying to be rude, but just so you're aware in the future...
Nit-pick aside, have you asked the advice of the friends you've made there? Have you asked anyone why they've added the cultural affectations they have? There might be an intended purpose aside from it being fun. If my dojo adopted a tutu and zoro mask I wouldn't feel comfortable being forced to wear that...in which case I would either look for some intended meaning which justified the behavior, or I would go elsewhere while trying to maintain ties with friends made.
I'm reminded of the old saying if you love something set it free. You have an inclination to change your scene, if they care about your friendship they should probably respect that.