Yeah, eventually, PayPal do things like that to improve security all round. By asking you to link a card with your account, they can get a better idea that you are who you say you are. Especially if you are from a country that is high on PayPal's fraud list. I think you can use any credit card though. But if you can't actually get a credit card in your name, you can probably get one of those pre-paid credit cards and use that. You would just have to add funds to it though obviously but yeah, that is one working work around of course. Good luck!