Costco "GM Supplier price" is $300 more than actual GM supplier price!

I was going to buy my a Chevrolet using Costco to get the $300 gift card.

However, I noticed that the cost of the car on GM’s Supplier Pricing website is exactly $300 cheaper than the price of “GM Supplier Pricing at Costco.com.”

Seems a bit fishy? Or am I doing it wrong?

Real supplier discount price: https://www.gmsupplierdiscount.com/ip-vpp/gm-showroom?site=sup-build
2017 Chevrolet Tahoe
Style: Sport Utility, Rear Wheel Drive
Trim: 2WD LT
MSRP as Configured1.$53,540.00
GM Supplier Discount Price$50,599.31
Purchase Consumer Cash2.-$500.00
GM Supplier Discount Price After Offer: $50,099

Costco Auto Program:
Invoice MSRP
Base $49,204 $52,345
Options $0 $0
Destination $1,195 $1,195
Total $50,399

The Costco gift card doesn’t require you to accept Costco/GM Supplier pricing. The latter is useful on high-demand, low-supply models that recently came out, but on other models, you can do better.

Yup, and I negotiated to “$2500 below supplier pricing,” which is not too bad, but that “supplier pricing” is $300 more than it should be…

You can upgrade to Costco executive membership at any time to qualify for the $700 card.