1. You have a mailbox, in a mail room and knowing where that is could be crucial to your existence,
2. There is probably a fridge in your departments lounge that you can keep you lunch in and even a microwave use so you don't have eat lukewarm leftovers.
3.There is a room in the library just for grad students, so you don't have to find a spot among all the undergrads who are using up the power outlets on the first and fourth floor just to play online video poker.
I guess there is a learning curve, huh?