That would be amazing, but unfortunately we handed over our freedoms to the government that will still want taxes in the 'official' currency regardless of the will of the people. The government also really really wants to be able to print as much money as they want to in order to control the economy (for the better or for the worse, depends on who you ask). Also, an even more pressing problem is that we handed over the means of production to corporations, so we wouldn't be able to survive by just trading with other people... (some would be able to, but we wouldn't be able to produce enough food for everyone, moreover think healthcare, basically a lot of people would die in result). The only way for your idea to happen in reality is to dismantle the system, effectively reducing the trust in official currency to nil, and that has happened a lot of times in the history of the world, so we just need to damage the system first and the currency shift will happen naturally.