There's a joke/urban myth that it's the law in Wisconsin that restaurants have to serve a slice of cheese with apple pie.

We did used to have a law that oleo (margarine) had to be sold undyed, which made it a sickly-looking blue-ish white. This was to protect the state's dairy industry. Only butter could be yellow. People near the borders used to bootleg yellow margarine back across the border from other states. The law was dealt a mortal blow when one of our state representatives publicly took a blind taste test in order to prove that butter was better...

...and failed. His family had been worried about his health, and was surreptitiously substituting yellow margarine for butter in their meals. (In an amusing historical twist, now that we know about the danger of transfats, we know that butter is indeed better.)

I think it might be an “older people in the south” thing. (Like all boomers and older I’ve talked to about it know about it, usually not younger) I worked at a diner for a bit, and it would be Silent Generation types that would order it.

It’s pretty good, but real cheddar would be better. It’s that similar salty/sweet combo that makes French fries and a McFlurry better than sex.