When you look through Amazon & Walmart, you are looking at a "marketplace." Amazon & Walmart will let anybody that claims to be a vendor sell through this marketplace, and take a small piece of the sales.
With this model, you get many fly-by-night discount drop-shippers who offer no service to speak of, so pricing is all over the place. One place may sell the more expensive model for less than other people sell the cheaper model. Another place overcharges for everything hoping to prey on people's stupidity.
The only way to get a clear picture of the pricing is in an apples-for-apples comparison. Make sure you are looking at "Vendor A" for BOTH versions of the grill.
It's also possible that one version is discontinued. Some of these fly-by-night vendors will charge a premium for the discontinued model hoping to prey on people who want THAT specific model for some reason. I've been bit on that before myself. At one time I wanted a second cooler to match one I already had, but it had been discontinued. There were plenty of new ones to be had on Amazon, just at a 2X what retail was before they were discontinued.
Putting 10-ply tires on half ton trucks since aught-four.