It is also a misconception that when paying with BTC person is avoid tax, maybe in some countries this can be the case, but we have VAT (value-added tax) in EU from 17% to 27% (Hungary) so every time you pay/buy something you pay tax. I buy some things from time to time with BTC, and I think VAT is quite a sufficient contribution to the state on my part.
Paying nearly 10% sales tax on every purchase in the states already seems oppressive. Of course, we're expected to pay capital gains taxes up to 37%
on top of sales tax. And if you trade or invest as a business, you owe an additional 15% in FICA taxes on your Bitcoin gains. It's just jaw-dropping when you think about it!
So, I don't blame anyone for spending their bitcoins to avoid taxes. Especially in the US, where most of our taxes are paying for really horrible wars and military expenditures from decades past anyway. The notion that our tax dollars are mostly funding vital services is a fallacy. It's highway robbery, that's all.