Cryptocurrency is very young. While its hard to say if BTC or ETH or something yet to be invented will be part of the digital money future, it is absolutely reasonable to expect this technology will have a role in the world. Of course people will make and lose "quick dough" but that's like saying the web failed because some idiot made or lost money on Pets.com or AOL stock.
Trade volume just means that the idea is in circulation, people of many walks of life are seeing what is there. Feel free to ignore those people, but to write off the entire concept as "about making quick dough" is asinine.