[borispavlovic]

There will always be ways to evade taxes and the problem with Italy, Greece and other southern societies is not technical but a weak government which can't impose the already existing laws to their citizens, public workers and politicians themselves. Going cashless is not an excuse for an incompetent tax office and Ministry of Finance.

[sametmax]

I don't know for Italy, but in France, you litteraly can't start most business without doing 20% of your money off black market.

Once you are big enough, it gets easier and you can go full legal, but to start, it's terrible.

[lmm]

There will always be ways to evade taxes, but the harder we make it the less tax evasion there will be.

[AnthonyMouse]

You could also say "there will always be crime, but the harder we make it the less there will be."

Technically true but useless for evaluating the cost/benefit of any specific proposal. If the question is, is it worth pervasive mass surveillance, the answer is no.