The problem is, if you start marketing certain films as something they're not, or toning down the taglines and the artwork in order to appeal to a wider market, the casual viewer could be horrified and be put off for life!
At least you know exactly what you're getting when you buy
Frankenhooker. Hell, the title alone should be an indication of what you've let yourself in for!
As for a man only aura, yes there is the traditional 'boobs and blood' masculine vibe to the vast majority of horror films (especially from the 1970s onwards), but you should be blaming the studios, producers, screenwriters, and directors for that. Plus, there are plenty of women out there who love horror films as much as men, whether it be
Friday the 13th or
Nekromantik!