But until I tie a wallet address with the physical world (like credit card or such), then they have no way of knowing that I own those coins. Also it will not b

But until I tie a wallet address with the physical world (like credit card or such), then they have no way of knowing that I own those coins. Also it will not be possible to determine from the blockchain only which amount of USD was paid for the said bitcoins, only that the transaction was on a particular day and that the bitcoins where worth, on average, a certain amount on that day. Furthermore, btc exchanges are not regulated and many are on foreign soil (out of reach by the IRS) so this average is mostly bollocks