@Jimmy
Although you are technically right, when you start deceiving people with your advertising tactics, you lose credibility. For a small store, if you are always "sold out" of the unbeatable prices that drew people into your store (even if you actually offered one), people will stop showing up because they just don't trust that you'll give them what they want.

In the case of Walmart, they offer enough other low-priced items to offset this, so their tactic is merely to draw "suckers" away from their competition, knowing that most people will eventually find something worthwhile anyway.

Either way, these tactics have led me to avoid Walmart during any kind of people buying time, which includes pretty much any weekday afternoon. To mean, dealing with the hassles of the lines and parking and angry people is enough to make me look elsewhere for a tiny percentage more (often less than $1 for lots of items I'm seeking.)

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Can we at least gently demand that they put how many items are likely to be available at that price, or at least "quantities very limited"?