1) They produce(or extract) about 5% of global production and no one wants that jeopardized with peak oil close at hand.
2) As with tobacco, they are more valuable to governments alive through taxes and fines than taken out back and shot.
3) It was not their rig, they only own 65% of this, Haliburton did the concrete and I forget the name of still another company involved, so even if liable, it is a shared liability and not solely theirs.
4) Large numbers of shareholders including elderly folks, mutual funds with hundreds of thousands of unit holders, pension funds and average investors hold BP shares and depend at least partly on the dividends.
5)No one can claim that they wanted this to occur and accidents do happen.
6)This was not even a producing well but an exploration well. Make the liability great enough and oil exploration will dwindle to the point of immediate shortages.
7) Trying to put a stop to a flow roughly a mile deep is no picnic and BP can't be faulted for not being able to do something faster that NO ONE on earth could do faster.