this is a good example of how individuals are fine to do things for the public good when they are consequential or at least compatible with the things in their best interest. We're willing to self sacrifice only so (and not very) far, so need to apply that goodwill very strategically. Another example: I commute by bike everyday, not because it's cheaper, healthy good for the environment (even though these are all true), but because I love it and it's so enjoyable - even it winter. Screw with the roads, or traffic patterns, or waste my property taxes, or neglect the bikes paths and snow removal enough and I'll either stop or move.