I'm a straight guy, but I also look at them from a fashion standpoint as well as music. If they all looked like old, fat men with leiderhosen, I don't think I'd like the band as much as I do now.
Something about a band's image really makes them unique, makes them cool. Japan's image was unique and cool. It definately has a factor on why I like them (because I'm into that free expression way of style...anything involving quirky fashion or hair) but I wouldn't say that I base them off of that.
I like them for Mick Karn's bass, the synths, the vocals, the chords and melody. But yes, their interesting appearance has a part in that.