It depends on their country rules.. There is not necessary to legalize the cryptocurrency.. Because it is not like a fiat currency.. it only a online currency we can only use with electronically .. And also it's price is not stable like other..
That's true, The legalize or illegalize of bitcoin depend on the country rules, so now, you can see that they're only few countries legalize bitcoin officially, I said officially because there is some countries, which people didn't know yet if the bitcoin is legal or not. I think the reasons of Illegalize this crypto, because of the high potential of it or maybe because the high volatility of the price.