Sure, I'm not always thrilled with how the government uses my tax dollars, but I have yet to see any anti-tax activists not using government services (well, except for the folks who live off the grid, grow and hunt their own food and never ever use public roads, but Grover Norquist that ain't).
I hate the process.
I understand the "do your own math just in case you don't trust the government" but it still sucks. I hate the loophole-ridden laws that complicate filing. I hate that it's bad enough it can support a giant tax-preparation industry. I hate the added computation that the federal government's unwillingness to deal with domestic partnerships introduces. I hate how the process not only makes it easy to cheat on your taxes, it practically encourages it. I hate the huge amount of unpaid tax that's sitting out there.