The drive to have the World's Largest Something-or-Other seems strongest in the Midwest, especially upper midwest. The world's largest Muskellunge is in Wisconsin.
Ohio has the World's Largest Basket at Longaberger headquarters.
You don't see New England represented much, though we don't seem entirely averse to roadside architecture in general, such as this one in Raynham, MA.
We did have one here in Manchester, the Moxie Bottle House. I still remember it, though it was in terrible disrepair by the 1970's.
Likely for cultural reasons, though I can't put my finger on it, quite, the other major areas represented on the list are the Canadian provinces across the border from those American states, New South Wales in Australia, and New Zealand.
Tacky Tourist Photos.
Strange and Unusual Buildings.
and the Wikipedia article on Novelty Architecture.