Imagine a marketplace where all nominal money prices are the same for products (for tax purposes), but you gain and lose "reputation" in the form of a Bitcoin style transaction.
Case 1: Those who have provided the most value in actual wealth (goods and services) to others, gain reputation (repcoins?). The money price could be $1, and that is what anyone who pays taxes, calculates that tax, based on. Say you buy a used laptop for $1 + 2 repcoins. You calculate tax, based on the $1.
Case 2: One might even ostensibly "collect" dollars with particular characteristics of serial number or whatever, so that you buy the "collectible" dollar, for $1 + 2 repcoins and the laptop is a free gift. That way, no one could accuse you of tax dodging. You paid for the product you wanted (the dollar) They threw in the laptop.