If there's absolutely no demand for the IRS then this "pet" is vanishingly small. No demand for the IRS? As in, everybody would trust everybody else not to try and free-ride? It doesn't seem likely. But who knows?

There's actually evidence (that I'm too lazy to dig up) that people do tend to voluntarily contribute more when the public good actually matches their preferences. gasp That's a real shocker isn't it? Maybe that's why I'm too lazy to dig it up.

Also, it's not entirely unreasonable to predict that like with crowdfunding... maybe government organizations would start offering some type of rewards to contributors. In other words... the carrot might gradually replace the whip.

If you're intrigued by the possibility then here you go... razotarianism.

Sorry about that. I made my point poorly. What Epictetus was doing to pragmatarianism is exactly what I would want him to do to any government plan. It should be just as difficult for the government to implement any of its plan as it is for me to implement my plan. It's great to have more, rather than less, people inspecting a plan for problems. According to Linus's Law... given enough eyeballs all bugs are shallow. Allowing people to choose where their taxes go would put a lot of eyeballs in the public sector.

Regarding your second point... it's addressed by the comment where I brought up the example of putting a man on the moon. Also, wouldn't you guess that there'd be less demand fluctuations with the public than with presidents or congress? The public really doesn't switch back and forth between conservative and liberal like presidents and congress do. I'd think that, for the most part, the aggregate demand for most things would be a lot steadier than the "demand" we get from our seesaw government.