If you've ever shopped at dollar stores they are often understaffed with a long line, no self-checkout, and a single cashier on duty if at all. If you argue about pricing you will hold everyone up in line, maybe get dirty looks and possibly wait an hour for someone with the authority to come and clear it up. Another person in this thread also mentioned that they got screamed at and chased out of the store for "causing a problem": https://news.ycombinator.com/item?id=46182451