why do people even care about tiers?

Tiers mean absolutely nothing, they're just a small ego-booster that insecure kids use. No one cares if you're in a "top tier" frat. Just focus on your friendships with people you have in your frat, and the fun you have at parties. Literally nothing else matters, and only your friendships and fun are worth anything. Tier achieves nothing and is simply an annoying concept.