Online travel agencies (OTAs) have grown exponentially popular, and drastically altered the travel industry by expanding hotel distribution channels alongside other travel related-services. This paper discusses potential concerted practices between the largest hotel chains in the U.S. and the two largest OTAs, Expedia Group and Booking Holdings. The paper explains how Most Favored Nations (MFNs) contractual agreements between the large hotel chains and these two largest OTAs have resulted in higher prices to unsuspecting consumers while also discouraging potential competitive entry into the online booking industry. The paper recommends increased antitrust scrutiny of these MFNs, and their attendant harm to horizontal OTA competition and consumer welfare in the online booking of hotel rooms.