Russia is simply afraid of anything that is not created by them. Russians do not like and do not trust Europe, or western civilisation in general. So they way of thinking is something like that: "wait - we did not invent bitcoin so it is probably creation of western society to control and enslave our economic system, lets ban it!". And sadly now Ukraine is following the same idiotic way...
That's not really 'idiotic' if you put yourself in position of any leader of a country with fragile/unstable currency.
Also, once you officially allow something, it's not easy to undo, especially if it gains popularity. So it's a safe option to ban something at first and if it turns not to be much of a threat, change the regulations to more friendly.
