Hey, we've all thought of this scam before. It was the first joke my friends made when I started writing barcode software years ago. "Yeah, I'm gonna go shopping with you. You can make new barcodes and get everything for free!"
Let's set aside the moral, ethical, and spiritual issues for a moment. I can make more money selling barcode software than I can steal using barcodes to rip stores off. Big Fat Duh.