Given my extensive experience with the (lack of) customer service at Walmart, people often won't bother to price match because they don't want to wait 30+ minutes for someone to flag down the manager, check the prices, etc for a small benefit.

But when there's a big price difference, say on a high-ticket item, it's totally worth the time because you can save money while walking right out of the store with the item, instead of waiting on shipping.