It is very similar to a person that has a Swiss bank account. The consumption of that person is a stimulus for the economy, so government will welcome you (A rich foreign customer). They will charge the car or house dealer for income tax, but not you
I can see many problems with taxation when merchants all accept bitcoin payment, since their bitcoin income are not traceable in current accounting system. One woman on the senate hearing session raised this question, but it seems so far no one have an idea how is that going to be handled
Sooner or later the merchants will have to spend that bitcoin moeny somehow or take a profit, unless they are going to pay all of their suppliers, employees and owners with bitcoins, there will be money traces somewhere when bitcoin is converted into regular currency.
Or our government can just switch to use tax and ablolish the completely broken and unfixable tax codes. It is kind of like VAT on anything and everything you buy. It will save all the wasted time and money (I hear $500 billion?) to try to figure out the tax code and pay the correct amount of tax every year. The government will save money by laying off 90% of IRS agents. There is no more tax cheat and loophole for the wealthy and corporation that can afford to hire accountants and set up off-shore accounts. It will encourage savings. It is fair, the more you spent (have the money to), the more you will be paying and lower income folks can get some kind of credit to off-set the use tax up to a certain amount for necessity. I can only dream...