I think the mother is missing the point a little bit, that the school is teaching her child about consequences (whether intended or not), because the real world there are consequences for everything!
It would probably do her child more of a favour to teach him to accept the reprimand with good grace, apologise, and not repeat the behaviour. We all 'accidentally' do something wrong in our lives, but we are still responsible for the outcome, and responsible for modifying our behaviour accordingly.