[Principled]

One reason for impossibility is the difficulty of calculating the tax.

But the same is true of a light bill or a copier bill. That doesn't make it impossible to include amounts in prices to cover light bills and copier bills.

[justshutupandtakeit]

No they are not the same. Not even close those are much easier to calculate. Apparently this difficulty is beyond your grasp as well as how prices are formed.