That's a sales tax and I think that's what governments will need to do: Go back to taxing tea 3% instead of the 50% income tax.
Discussion
I'd happily take that deal. The problem is that in addition to any sales tax, current US lax law requires you pay taxes on "capital gains" due to bitcoin price appreciation.
Yes because you are avoiding the hidden tax of inflation.
I'm talking about when inflation is no longer a viable option to fund government expenditures.
The sales tax will probably closer to 15%.