I have no idea about a normal game...but I know in the Super Bowl, they tend to use a brand new ball for every damn play.
They print the lettering on the balls in advance too. Chris Berman from ESPN had a ball that said "Super Bowl XXVII: Bills VS. 49ers" ... of course, the 49ers failed to make the Super Bowl that year....Super Bowl XXVII was actually Bills VS. Cowboys....but they had the footballs printed already in anticipation of the 49ers being there.
They print all the championship T-shirts and hats in advance too, and the ones they don't use are donated to 3rd world countries. Actually it's a funny story, there's a soccer team in Africa that wears the New England Patriots' Super Bowl Champion t-shirts as their official jerseys.