I am not sure of the exact answer but I have earned a little with crypto currency. When it was started in my country, every one was aggressive and forcing to learn how to earn from it. It is a digital money, that is what I really know. I benefit on earnings by joining free sites that I will be mining satoshi, let it grow, meet the minimum and withdraw. I put it on a coin wallet and I used the earnings for mobile load. I had been earning from it. I even joined Steemit, a blogging site that pays you with cryptocurrencies. I got my earnings this year. I think it is true we can earn, but the real earner are those who are earning from investment. There are people who let their balance sleep until the value is increase, they will withdraw their money. I do it too but at present I stop earnings from it.