I would who heartedly opt out of tax payers money going to such things as asylum seekers, illegal immigration, abortion etc.. Anyone who champions those can foot the cost.
And the topic is not solely aimed at the US and UK. Switzerland is more direct democracy, so important public decisions are put to the people via a referendum, the people decide. Like I said, where there's tax payers money involved, take that idea forward so those that vote "yes/for" can share the cost of that decision.
I am sure there are plenty of people who want to know how people vote individually for their purity and enemies list. I am not one of them. If you don't want to support anything, have no taxable income. Problem solved.