Two questions 1. If customers are scanning their own goods, doesn't that make it likely they will occasionally, for one reason or another, miss a scan? That's

Two questions 1. If customers are scanning their own goods, doesn't that make it likely they will occasionally, for one reason or another, miss a scan? That's huge for Walmart's margins. $15 total expense per hour labor saved is not that huge a savings. 2. How does this work with items sold by weight? Have they installed new scales that can allow you to select the item weighed create a barcode for the price of that weight of that item?