Why can't Expatriates use their American Credit Cards

I had been using my foreign address with my American credit card in the past, but just after the current update broke seeing Panasonic RW2 files in Finder, I discovered that I am no longer allowed to live outside the US and buy things from the App Store and presumeably not from the iTunes store. My credit card company has both my foreign address and my foreign phone number on file.

I can see there being a problem if the credit card company's address for the customer did not match the location of of the user, but this is not the case with my card and card company and I have bought things from US companies without this problem. I should be able to attach the account to the US store with the US card or I should be able to use the foreign store with the US card which has my foreign address.

I think there are many people in my situation, Americans living abroad who keep their banking in the US and I guess Apple feels it can throw us away as customers. I'd like to know the reason. It's not the issuing banks.

This also means, of course, that I can never buy an iPhone or an iPad, and will have to stick with Android phones where I can buy apps on line.