Another econonmic (but non game theory) perpective on this is that non-vaccinators are incurring a cost to everyone else (paying for health care, the risk of ge

Another econonmic (but non game theory) perpective on this is that non-vaccinators are incurring a cost to everyone else (paying for health care, the risk of getting sick via failed vaccinations, gov't costs for health campaigns, etc), thus imposing a 'negative externality'. The general approach to preventing a negative externality is to tax it, so that before you can take an action that 'costs' everyone else, you pay that much into the system. So raw economics suggests that we figure out the marginal 'cost' of adding one unvaccinated person, and offer to let them 'choose' not to vaccinate if they pay the cost to society up front. Of course in reality that's all bollocks because the cost goes up once you hit a tipping point (as you said), and trying to identify a monetary damage per-non-immunized is sure to result in a WAG. Fun problem to think about though.