Well in the case of a listed building they DO sometimes force them to rebuild it, at huge cost. Making the culprit pay for every penny of a replica wouldn't put the henge back, but it would be something better than leaving it flat. And if EH were deliberately nit-picky and asked for it to be precisely to the contours it used to be, no argument and no negotiation, it might cost £100K to do - i.e. far more than the maximum available fine, which would be satisfying.