Guys who would make fun of girls for sexual inexperience are terrible people, and when girls do it to other girls it feels even shittier. Guys who shame girls who haven't had sex want them to feel like they aren't doing their job, which is to be sexually available and attractive to guys. (And never mind if they are gay, or just uninterested.) Girls who shame other girls for these reasons are helping those guys. They are saying this: You are not accomplished where it matters, and I am better than you. I have proven that men find me attractive, and that is what counts. These people, boys and girls and men and women alike, are all dickheads.