Back when margarine smugglers from Illinois used to work the Wisconsin 'cheap dairy' markets.
Streets of Old Milwaukee...
https://www.jsonline.com/story/news/special-reports/dairy-crisis/2019/08/28/protect-dairy-industry-wisconsin-tried-keep-yellow-margarine-out-oleo-run/1950671001/
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One last remnant of Wisconsin's anti-oleo campaign is still on the books: Restaurants and public institutions are barred from serving margarine as a substitute for table butter unless a diner asks for it or both butter and margarine are offered. If you're caught and convicted, the maximum penalty is a $500 fine and three months in jail for a first offense — and up to a year for each offense after that.
The penalty is similar to those for class B and C misdemeanors such as harassing phone calls or electronic messages; disorderly conduct; food stamp fraud of less than $100; and letting a prisoner escape.
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