Aside from it could be fearful if the exchange itself is being hack and that your tokens or coins are on it and being taken away already. Bitcoin is very risky and volatile, anytime the price might drop that will lead to a huge loss, I think that's the main reason why people are scared to invest in bitcoin. I think it's better for them to make study and gain more knowledge about bitcoin before they invest so that they have no such things that comes into their mind about it. It doesn't matter whether Bitcoin is legalized in all over the world or not, because people want to buy Bitcoin for a fiat currency of the country they live in. I can't call this factor a scare. It is just an being careful of avoiding a potential losses.