Not true...Look at the chipguide under Iowa.

http://www.chipguide.com/cgi-bin/search/search.cgi?id=iowausa

Praire Meadows is a casino and Racetrack. Winnavegas is an Indian casino. They have Diamond Jo in Northwood listed as Riverboat but its right off the interstate and I did not see any water. They had a watertower. LOL

So sorry, Iowa has various types of casinos. I traveled went through 10 of them last month.