Sexism in music

Why is it that bands who have female vocalists are bands with a "token chick singer" while bands who have male vocalists are just regular bands? Why is it that in music reviews, (male) critics can talk purely about the quality of a band's music and performance if they have all male members, but if a band has a female member, often times the critic MUST make a comment on the attractiveness of said member, irregardless of her musical abilities? Why is it that some males don't want to listen to bands with female vocalists (even the ones who try to be "heavier" and thus "more masculine") because they think that it's "gay" or it will make them look like "pussies"? And why is it that women who bring up these issues are just being "bitches" who get "offended" too easily?