Everyone can use bitcoin in different ways even it in good time or bad time. Bitcoin is not variant to fiat or any form of money, as long as it have a value it will use in many ways
To be honest it is not only a currency but it is the future maker and it can be use by everyone bitcoin is the freedom you can use it as you want to use, no one is going to make you bound while you are suing bitcoin, now bitcoin is being use globally anyone can use it for any purpose like other kind of money is being use,. Bitcoin does not have any kind of connection with terrorism so if people are using it for such illegal activities it is their own choice I am using bitcoin to secure my further it is my own choice so feel free mate.