They don't have access to the internet. Only some apps like Facebook, if they have access at all.
Eh? Internet good enough for Facebook is Internet good enough for getting a wallet. Using Facebook would use up a lot of data, so it's not like getting a wallet requires a better internet connection than it.
I think he was referring to the 0.facebook version of it, which doesn't charge the consumption of data transferred, and doesn't even show images or videos, just text.
If people in these countries don't have fixes internet connection, or even enough money to pay for basics, i honestly doubt they can or would pay for mobile data packets.