Dude, I have news for you. This stuff happens on every lake in the country that'll float a pontoon. And it's not just the visitors; locals do it to. I've seen it on Lake Mead in Nevada, I've seen it on Lakes Murray and Marion in SC, I've seen on the Intracoastal Waterway in SC and NC.
But you guys go on thinking it's just Chicagoans visiting WI, and that the boaters and fishermen on every other lake in North America are law-abiding, license-toting, Coast Guard Auxiliary-inspected, DMV-registered, and have both working tail lights on the trailers and no beer in the boat.