Checkout 51

Hey guys, I just recently downloaded Checkout 51 on my phone as I figured I might as well save a few bucks from doing groceries every week. For those of you who don't know what it is, it's an app that gives cashback on certain products. So if you bought a product that they are offering cashback on, simply take a pic of the receipt and upload it and voila! My question to you guys is this: I work as a cashier and I was wondering if I could take copies of receipts of other clients and upload them as my own? This would speed up the cashback process but is this against the terms? How likely would my account be banned for this?