Was that in one or more of the "Frontier" iterations, there was a "family-oriented" feature of the property called The Frontier Village. The Silver Slipper (initially called the Golden Slipper) was built on part of The Frontier Village location, so, both casinos shared ownerships, parking lots, patrons and 3 or 4 chips!

Take a look at this link to a history of The Strip: http://www.lvstriphistory.com/ie/index.htm

Jim Follis