Wouldn't that mean we are regressing in types of trade? When we had very little structure to the economy people traded cows for a tool or something like that.

That's a weird thought. If we accept something like that then wouldn't that mean rejecting our current economic structure?

Obviously not all crypto's are the same, but with the current crypto's inorder for Grandma to use it for her groceries, the demand for the currency will have exploded, and since they can't just create new currency, the price will also have had to explode, so does that make it a ponzi scheme? Everybody making money off the last one in? Maybe not but hopefully I make my point.

The original premise of bitcoin as a currency that could eventually replace fiat is a fantasy of delusional libertarians that don't completely understand our complex monetary system based on debt, interest rates, and growth. In this respect cryptocurrencies are effectively worthless. Their volatility makes them unsuitable as a carrier of value, and much of their movement is based purely on manipulation. Without the gigantic players like those in equities and treasuries there is nothing to bring the market to balance. It takes longer for reality to settle in. Pump and dump is the name of the game, and eventually just as many people lose money as gain it in bitcoin. The run is over when new buyers willing to donate market cap disappear. Then the only thing to provide a floor is the cost of electricity.

However, blockchain technology itself is a revolutionary step forward in tracking and processing financial transactions. So in this respect we are only at the beginning stage of growth. Developments like smart contracts in Etherium, and large financial institutions starting to adopt the technology are significant investment opportunities. The key is to invest in the technology, and not insane financial theories.

There are multiple things going on with these cryptocurrencies. The acceptance of Bitcoin and Etherium in retail is growing daily. But also driving these things are the use of blockchain technology on a broader scale for use in corporate applications. Many of the crypto's are not exactly a currency but an investment in the adoption of blockchain technology. There are a number of well respected investment newsletters that are now recommending small investments (ie $100) in various crypto's which they believe will mushroom over the long term. For instance, Antshares is the only cryptocurrency approved by the Chinese government for commercial application. Based on a newsletter recommendation I put approx $200 into Antshares and it exploded to be worth 8 BTC at one point. It has since pulled back but I was able to take out about half (ie $8,000) and am letting the other half ride for the long term.