Most Helpful Guys
Seem unapproachable, unfriendly, or simply not attractive to the guys out on that night.
If you're always in groups guys won't approach, if you look angry/bitchy, they won't approach, if you look like you have an attitude or high maintenance, they won't approach.
Make it so guys WANT to approach you, smile, don't simply wait for them, act upon your crush somewhat, look at him, smile & have open body language.
Why can't you approach him & why do guys HAVE to be the ones? He's your crush, doesn't mean your his crush either, approach him, let him know you're interested. Just say hi & touch his shoulder then walk off. He should approach you later if he sees you.
Nobody is entitled to being approached by anybody else. Odds are if they won't approach you, they could be feeling intimidated by you, or the possibility of rejection, or maybe they have second thoughts and have somebody else they are thinking about approaching instead.
Most Helpful Girls
Guys rarely approach complete strangers. Even if you're friendly, presentable, and a good person - it's still a pretty rare occurrence statistically speaking.
That being said, guys are really sensitive to non-verbal communication. If they get the hint of a hint of the idea that you might NOT be attracted to them. They won't approach.
I think men approach you when you are by yourself. I got approached a couple of times in the last couple of times and each time I was approached, I was by myself. Guys never approach me when I am out with other males.