(CNN) - Fans aren't the only ones screaming about the National Football League's replacement referees.
Las Vegas is concerned the refs will hurt betting. Unionized refs are sidelined in a dispute over pension plans and work rules. Their replacements have been widely criticized for their calls so far this season.
Gambling experts say fans could pull back on their football betting if replacement refs continue to be used. They say gamblers don't like controversy... but add that betting was at normal levels during the first three weeks of the regular season.