When a product is listed with the incorrect price at Walmart, customers are entitled to receive the difference back up to $20. This means that if you purchase an item that is priced at $10 more than it should be, you can get a refund for the difference. However, if the price discrepancy is greater than $20, the decision will be escalated and determined by the Walmart manager.
On the occasion that the price difference is over the $20 threshold, you may need to show the advertised price or walk to the aisle with the store manager to show where you took the product from the shelf. This is to ensure that you are not attempting to take advantage of the system.