As far as I know, they only use PP. I find PP a safer solution than buying with a credit card, but I understand people may have issues with either method.
Anyway, a solution would be people giving you the money and you buy Kiva gift cards for their use. The problem is if/when they want to cash out.
Yes, I agree, I prefer PP too, but I can hardly ask my friends to start up a PP account just for Kiva. But your idea of buying gift cards for them is great. I 'm convinced quite a few friends/family would be interested!