is not that bitcoin able to change the state of its users which effects also on the state of the country's economy, why even banned hemzzz 
Probably they are in fear of money laundering. Since most of the countries has no regulations yet when it comes to crypto currency, then the opportunity for the black market people to use this is high. Well it happened before in some countries already so the chances of it happening again would be huge. Well this is just my opinion though.