Sorry if this topic has already been discussed, but I did a quick search and nothing related appeared to me.

After reading This I have decided that the bars on my campus are complete bullshit.

Every bar here is 21 and up, and that's fine. What isn't fine is that girls 18 and up are allowed in. I am thoroughly pissed. Most of my friends here at school have recently turned 21 and me and a couple others are the only remaining 20 year olds. This leaves me to sit around and do nothing when all of my friends are out at the bars. When I ask the doorfucks why I cannot go in and the 18 year old girl can, they tell me "you just can't."

Why is this allowed to happen?