Sometimes the practical choice is the responsible one. It may have been for you, because if you just drove off, the people would have called the cops on you, thus giving you a criminal record and a punishment that would cost you more than it would've if you just pay the insurance.
So is it nasty bill or punishment and criminal record that will come back to haunt you? You chose the former, which is, in my opinion, the wiser choice.
Either way, this situation sucks balls for you and I can sympathize with you as a fellow Person Completely-Without-Money.