Why do metal heads hate Motley Crue and are you a real metal head if you listen to glam metal?

Answer 1

I suspect it's mainly because of their early look, with makeup and heels, but some just hate their music.

As for your 2nd question, of course you are a real metal head, even if you listen to only Glam Metal (metal is in the title after all).

Heavy Metal is hard to define (check out the HM doco with greats like Tony Iommi, Dio, Lemmy etc.), who all struggle to precisely define it. The best way I can define it though, is guitar orientated music, with a heavy pounded drum beat (which rules out bands like the Stone Roses), which makes you want to head bang, or at least nod your head repetitively... which is what Motley Crue's music does.