It's based on an unspoken 4 tier system. If you're broke, or just have very little money, you're at the bottom. If you're broke/have little money, but know powerful people, you're one level up. If you've got the money to pay all of your bills, you're one step above that. If you've got the money to pay for all of your bills and you are a powerful person or have connections to powerful people, you're the highest tier.
And to think, if I had the money to go to med school when I was going to college, I would be one of those white coat bastards you love to hate... But now, I'm just a bastard. 
