At least here in Uruguay, the answer is yes.

Don't only think of the classic "poor", think of: - people earning 500 dollars/month (lower middle class here) which Visa and Mastercard don't accept as customers;

- young people (under 18 or 20) and women (that's A LOT of people);

- people in informal work agreements (that's 1/3rd of the population here), black and gray market, which cannot demonstrate their income and avoid taxes.

Isn't that paypal's business model? They're doing OK.