Menards does have huge cart corrals. The corrals have never been empty enough for me to confuse it for a parking spot, but without carts it would fit a car just fine. It's odd that they don't have dividers. Then again Costco doesn't either.
I had to check the Menards website. I knew Menards sold everything but it never dawned on me that they literally sell those carports. I didn't know that's what those structures were called either. That's a good point about the large lumber carts.
Menards corrals are literally carports they sell in the store (and hence covered which is nice).