How about free for people in China, and other countries where Paypal is either very difficult to arrange or downright impossible?
AFAIK, in many places the theoretical ability to be able to sign up for something like Paypal is almost useless because of all the other things that one needs to do, or have. For example, there may be 'credit cards' in China, but few private individuals can use them. Even if they have them, they may not be able to do internet transactions using them, and even if they could, they may only pay for things in RMB (renminbi, the Chinese currency), not USD (US$).
While it would certainly be a good idea to ask Paypal about this sort of thing, IMHO the answers you'd get would be only partial, at best, since their will (naturally) be interested to put a positive spin on it, and because it's likely they don't know all the difficulties involved.