I think there are nuances to the question of which services someone can support, which require deeper consideration than just "are they (involuntary) collective

I think there are nuances to the question of which services someone can support, which require deeper consideration than just "are they (involuntary) collective systems". If someone gets heart disease because of a bad diet, you may not want there to be an involuntary collective system that covers the cost of their medical treatment, since you don't get any direct benefit from this. (For comparison, a voluntary health insurance based system, with multiple competing private insurers, wouldn't have the same concerns attached). In contrast, if someone decides they are a pacifist and doesn't want to pay for the armed forces, but they live within the same borders as you, then they will gain the benefit of military protection that you are willing to pay for. That's not to say I personally agree with that distinction, though. Ultimately a life is worth the same whether it is ended by heart disease or a foreign soldier, and I believe that people in a society owe each other a duty of care to spend "reasonable" resources on protecting each others lives. However, I think that is a moral position, and someone with different morals could consistently draw a line between the necessity of involuntary military funding and the non-necessity of involuntary healthcare funding.