I am sure the profit margin is taken into account, so you won't get an ultracheap Pepsi unless it expires soon. Similarly, I expect it to consider economic viability, so it won't keep raising prices unless people are willing to pay them. Of course, you never know what the model actually does or what goals it follows (maximizing profit is a good guess, though), or how bad the coding is. The program might be very versatile and robust, or it may break when you show it a QR code - how can I know? Probably something in between.