Yes, and that's a dataset of n=1. Things like littering have a million different factors go into them, including culture. It's not unreasonable to think that in other cultures, increasing the incentive to litter would in fact increase litter.

An exponential fine on littering would, however, absolutely destroy any incentives on littering. Starting with $10^n, where n is the n'th time you are caught littering. Also a corporate fine for dumping trash and waste illegally, $1000^n.

It really is not hard to take care of your environment!