Some countries do not like the bitcoin as it can destroy their own economy due to that they do not want it in their own country..
This is a compelling reason, this is because the bitcoin can not be controlled. of course it could damage the country's economy. The best possibility is to make your own digital currency that can be fully controlled.
By seeing that bitcoin is now not yet popular among people in this world or I could say that people who knew bitcoin are only the minority and honestly the pretty small amount of people in percentage it's couldn't really threatening a countries' economic. The impacts aren't that big to an economy when people are buying bitcoin there might be a time that they will exchange it to fiat again because their purpose of buying bitcoin mostly to get profit not to take advantage of its feature