Bitcoin value will increase if there are many demand on it.
I'm sure this will be the most wanted currency that ever live on earth
If all the Bitcoin users refuse the spend their Bitcoin and decide to just hold all of them, then the price of Bitcoin will not move. Bitcoin's price will not increase, it will not decrease as well. No movement will be detected until somebody decides to sell their bitcoin or until somebody enters the bitcoin world and decide to invest some money into Bitcoin.
I'm sure everyone will buy bitcoin and the value will increased exponentially
Doesn't the price go down when a lot of people are spending Bitcoin in shops that immediately convert those Bitcoins to fiat?