Tax fraud only became easy with the possibility of anonymous acceptance of payments. Now with Bitcoin you and everyone who produces intangible goods can officially complain about not getting preferential tax treatment.
Tax fraud has always been easy, why do you think restaurants/barbers/plumbers/etc. prefer cash so strongly?
The official line is that credit and debit cards have high transaction fees, and that's true (especially for very low and very high prices), but cash isn't free to accept (security, counting, counterfeit risk, etc.), and yet service industries universally prefer cash over any other payment method. Why? Tax fraud.
