[URSpider94]

That's already well established for barter transactions. Yes, sales tax must be collected and remitted. The amount is calculated on the fair market value in USD of the goods received. Tax must be remitted in USD. This is one of the reasons that national currencies are referred to as "fiat currencies," because the government dictates their use for paying taxes.

[Codhisattva]

That's not what "fiat" means. That's what "currency" means. (That is, if you can't pay taxes to defer the threat of state sponsored violence against your person then it's not valuable currency.)