No, they are not crazy, or at least not too crazy. WACKO is Wausau Area Canoe and Kayak Organization. This weekend is a citizen's race and recreational event down at the Whitwater park. People who love whitewater doing their thing just for fun and enjoyment. Still lots of fun to watch. Plus you can pick up a Gelato and some really excellent spring rolls at the booth between the county buildings.
Here is a teaser pic, there are more on the Flickr page.