When you start paying your own bills you will definitely see the point of having a credit card...
Lets say that after all your bills are paid for the month you are left with no cash in your account till the next paycheck, you then open your refrigerator and see no food...Do you think you are really gonna go till payday without eating? Also when you go to finance a car and they tell you that you have to get a cosigner because you have no credit built up...I got my first credit card at 18 and used it for gas for my car and paid it off every month when the bill came in and when I went to finance my new car I had no problem getting a loan. As long as you don't get it in the mail activate it and go max it out immediately knowing you don't have a job or anyway to pay it off they are a very valuable asset...