Will Apple disable your account for buying IAP abroad? I have an US App Store account from when they opened it, 2010 if I'm not mistaken ( I'm an early adopter :) ).
Back then I used "None" as payment method when I created the account because I didn't have a credit card.  I used a fake US address, as I live in Asia.

I've heard that you can do that, but if you buy In-App Purchases your account will disabled forever, because Apple allowed buying apps with gift cards abroad but doesn't allow buying any IAP from abroad.

But that was in 2010, what I want to ask is: are these restrictions true? Will Apple disable your account for buying IAP abroad?
On the "can you spend a Gift Card on In-App Purchase" part, here's what Apple says:  


  You can use store credit for purchases that you make in any of the stores or to pay for in-app purchases until it's gone.


As long as you keep using Gift Cards and don't run out of credit you should have no problem.

If you have or get a local credit card, and want to use it, you will have to either create another Apple ID to manage both stores, or switch to your local store and lose US store purchases, as you need your card and store country to match.

As Apple puts it:


  For example, only German credit cards can be used to buy content from the German iTunes Store and App Store.


This articles 1, 2 take on the problems and advantages of having more than one Apple ID for purchases and describe what you do in extension.