"This is the first time we have been alerted to this fact," said a statement from First & Goal, which manages the stadium for the Seahawks. "Upon our internal investigation this afternoon, we discovered the cups that are marked 16 oz. hold 20 oz. of liquid. Fans who purchased a 16 oz. beer actually received 20 oz. of beer for the 16 oz. price. Fans that purchased the 20 oz. beer received the amount they purchased."
They only have once size now (20 oz.) and it's .25.