If the crypto exchanges follow the law of the land properly and pay the appropriate taxes then it is not at all difficult to run a crypto exchange in any country.....As far as crypto-currency adoption is concerned, banks may very soon issue crypto-currency that is based on their own private blockchain and hold crypto-currency values like how banks from different countries hold each others fiat currencies...I can clearly see that once the government and the banks understand how much money can be saved by implementing this blockchain technology, then i dont' think it wont take much time to replace fiat with crypto-currencies. I am very optimistic on it.....