Believe me, poorer countries are the most exited ones about cryptocurrencies. Imagine a country with WAY, WAY more corruption than you can imagine, inflation, unimaginable taxes, a currency worth a few dollar cents and lots of poor people. The cryptocurrency dream is a light in the end of the tunnel. But I know what you mean, most people haven't heard of it yet. There was recently I robbery here to an exchange where the robbers were asking for the bitcoin (as if it was some kind of paper), probably because they just heard about it on the TV and that it was worth thousands (around 50k on our currency).
RE: The biggest problem cryptocurrencies will face before becoming mainstream (IMO)