Bitcoin involves a lot of transactions. Money transactions. Every country is trying to raise their economy specially nowadays. The government wants to involve in almost all possible money transactions and remittances for them to monitor, control and regulate. If they cannot do it will not help the economy. The government in some countries would rather suggest other form of medium for their transactions instead of bitcoin. It is also possible that because not everyone have knowledge in bitcoin making it useless to them. The government also wants to avoid the possibility that bitcoin can be used for money laundering and scams.