What causes the prompt to enter iTunes password when dealing with IAP?

Hi,

I am using Unity 5.3.4 and I've recently refactored some of my code to utilize the unity IAP system as I was working on other things and it seemed like a good time to do it.

I have everything functioning as I anticipated however I do have one problem on iOS.

I'm using the example code provided at https://unity3d.com/learn/tutorials/topics/analytics/integrating-unity-iap-your-game and basically stripped the code out that I didn't need and added the products I have available on my store.

On Android this works as expected however on iOS whenever the app is launched or brought back into focus after being minimized I am asked to enter my iTunes password. I'd like to prevent this from happening but I am not sure what causes it as I also do not save my password on Android platforms and this behaviour is not present there.

I assume that this is somehow caused by the initialization loop, is that correct? Basically I only want the password prompt to be entered when I select purchase on a product in my game or if the user is restoring past products.

Does this mean I need to initialize the store only when attempting to make a purchase or is there another way around this behaviour?

Or is there another issue somewhere else?