That's like saying most home cooking in the country is the same because everything comes from Walmart/Kroger/Meijer.

No, you're missing the point. A lot of casual restaurants aren't even really cooking any more. They just heat up prepared food purchased from Sysco.

https://www.thenation.com/article/society/restaurant-consoli...

"A lot of" and "most" are different things.

Yes, a lot of places are not making their own jalepeno poppers. There's still plenty of stuff being made from raw ingredients all over the place.