There are a couple of reasons that stores who are both brick-and-mortar as well as online are different:
Identify some of the reasons why stores who have a brick and mortar presence may be different online. To get you all started, here are a few examples.
1. Most times they have different inventories and plan according to those inventories
2. Some online stores are franchised and are not affiliated with the physical location
3. Sometimes stores offer the price cheaper online because they use a just-in-time system. This means they do not have to maintain a physical inventory like the physical store. Hence, they can offer the price cheaper because they wait until the order is placed.
4. Sometimes online stores work directly with the manufactures. Hence, the TV you spoke of may not actually come from a Walmart store, it may have come from the manufacturer if you had purchased it online.
Although I agree with you and have been frustrated by a similar experience, I hope the reasons I shared at least helped you gain another perspective.
(Please provide good auality and original response. Thank you!)