Seriously, I'd love to call myself an egalitarian and leave it at that. I believe that all human beings are equal in their fundamental worth. However as a bisexual* man, I find that it's better to say that I'm a feminist. Why? I want equal rights for all, but I recognize that the system still favors men. By saying I'm a feminist it doesn't mean I don't want equality for men. It doesn't mean I only care about women. I acknowledge there's an an inequality and use a word to bring attention to it. I don't like the patriarchy. I don't like the system we live in.
It's like #blacklivesmatter. By saying that black lives matter, you're not saying that other lives don't matter. You are drawing attention to a serious problem. Just because I talk about wanting to save the rain forest, it doesn't mean I want to burn all the others down.
*I consider myself bisexual, despite the fact all my relationships have been with women. I'm definitely open to a relationship outside of what I've experienced though.