Most of these unbanked people are from the rural areas and such regions provides lots of workers and most of them work outside the country. If a person in diaspora wants to send money back home and he realizes that his loved ones are unbanked, what will he do? So with BTC, such people may escape from the remittance high fees. BTc will open the minds of many people who receive.
Bitcoin network will be one of their choices if they are unable to access bank system. Altcoins will be one of their choices too and many altcoin networks can provide cheaper transaction fees than Bitcoin network, which means a lot for unbanked people who are not rich, don't have much money to spend and they do care more about how much they have to spend for each transaction in transaction fee.
Everyone on the internet require some private and fast Ttransaction, it'll surprise you to know how electricity is everywhere including the rural area.
Have easy access and self-control their finance and transactions without need to go to have bank accounts, time for transportation to reach bank offices are their biggest concerns. Privacy is important but it might be lower in their concern priority.