I don't agree with Adam Smith.
Bitcoin price is being determined by the free market, it worth what people are willing to pay for it.
The more the bitcoin price goes up, the more it becomes profitable to mine, which makes more miners to join the circulation, which increases the difficulty of mining a bitcoin, and makes it cost more to mine.
I think that the price of something is only related to how much people want it and are willing to pay for it.
During last year bitcoin miners were not really getting a lot out of mining bitcoins but with the recent surge in the price of bitcoin, mining bitcoins has become even more profitable then it used to be and now miners who have spent a lot on their mining equipments are actually making money, bitcoin mining is no longer a hobby but a profitable venture.
Right now miners are making a fortune that is why I find very doubtful they are going to move most of their hash power to other coins as they have threatened to do with the new fork of segwit2x, they have probably made more money in this year alone than in many of the previous years it will not make sense to throw that away especially since they are all competitors and if a miner moves to another coin then that leaves the road open to the rest of the miners to get even more profits.