1-month check up

Samuel had his 1-month check up today with his pediatrician.  Her first comment when she came into the room was "He's a BIG boy!".  He's 23 1/2 inches long now and weighs 11 lbs, 14 oz.  She said his height is "off the charts".  When I asked if his weight in proportion to his height was ok, she said it was perfect and that he's definitely not a chubby baby.  Hard to believe since he's been eating 4oz at every feeding for the past two weeks already.  He's going to eat us out of house and home already.  I thought that didn't start until teenage years?!?