Walmart's Walmart+ terms explicitly prohibit members from using the membership or its benefits for the purpose of resale, rental, or delivery to other customers. This means you cannot purchase items with Walmart+ benefits (like free shipping or delivery) with the intention of reselling them.
This has been discussed heavily in other threads perhaps you can find more information there. There is a “clear limit” they call it “MAX” and you cannot go over it on Walmart + Early Access items, BF, CM, Walmart Exclusives and some have reported SW sets.
Self-control is what prevents you from placing multiple orders. It is not the retailers responsibility to enforce this. Most people that “go for it” and exceed the limits report that they don’t value the service anyway while others like @exciter1 can’t live without the Burger King discount.