I am surprised he did not get fired! You absolutely did the right thing. If he makes your life miserable for it, he was never a good friend to begin with! I would ask the manager if you can not share many shifts with him for the time being, if that is possible! He may have stolen it just to see if he could get away with it, and now is disappointed with the outcome. Do not let him take it out on you kiddo - you did the right thing.