I have this same issue only I was answering a phone call. I had wiped of my screen after hanging up while the game was reloading and suddenly I had purchased a $29.99 bonus pack of stuff I didn't even want. It shouldn't have been able to do that since all purchases require my password to complete.  I have been trying for almost a week to get someone from support to answer me on whether or not I can swap my accidental purchase for something I can use and they have been ignoring my emails.

Has this been resolved? Ive had the same thing, purchased something while my phone was in my pocket