I wish that we lived in a world where people could always control what their dollars directly and indirectly funded, but we don't, and Christians only seem to care when it's their money and something they believe is immoral. Would most Christians support another person's "rights" not to have their income tax fund foreign wars/actions they morally oppose? The vast majority of Christians would certainly not, and for that reason I cannot support their right to pick and choose their healthcare funding according to their morals. If they want to broaden the debate, and argue that everyone should be able to refuse to contribute towards things they believe are immoral, then I'll be happy to support their cause. Until then, we might as well all be stuck in the same boat, until we together pick a course that gets us to a better land.
P.S. - Of course beyond issues of morality, there are lots of other purely lifestyle related costs we make others pay for. If a couple chooses to have 5 children that can incur public schooling costs of $600k (from kindergarten through high school), that burden is disproportionately covered by those who choose to never have any kids or have just one. As a society we have decided to pool our resources, accepting the many potential inequities, injustices, and betrayals of personal conscience. We can't have it both ways.