While free drinks might still freely roam the casino floors, select MGM and Caesars properties are policing harder at the bar. (David Becker/Reuters)

This post has been updated.

The free drinks at casinos make everyone feel like a winner. However, several casinos are killing the buzz: Select properties in Nevada, including Las Vegas, are no longer providing gratis cocktails to bar patrons who are drinking and yakking more than drinking and gambling. The new mantra: Must play for a cocktail.

“We are making a concerted effort to reward our larger-spending customers,” said Rich Broome, executive vice president of communications at Caesars Entertainment. “This discourages people who are just looking for a free drink.”

At the moment, the new policy applies only to casino bars with video-poker machines. (To clear up any misunderstandings, the bars never provided complimentary drinks to non-gambling guests, though the rule was not always enforced.) After a short trial in late 2015, Caesars introduced the comp notification system at nine properties throughout Nevada, including those in Las Vegas, Laughlin, Reno and Lake Tahoe.

Ardent Progressive Systems and Games, which created the Ardent Complimentary Validation System used at Caesars, has also installed the technology at the Venetian, the Palazzo, Hard Rock Lake Tahoe and Westgate, formerly the Las Vegas Hilton. Also on the Vegas horizon: Golden Nugget, Treasure Island and Hard Rock.

Within the last year, MGM Entertainment has rolled out a similar program at MGM Grand and TopGolf, an entertainment venue on the Strip. A company executive said that MGM could expand the program to its casinos in New Jersey and Mississippi. (Gamblers in Michigan and Maryland don’t have to worry; by law, they were never allowed free alcohol.)

“In the 1950s, the industry was trying to incentivize,” said Alan Feldman, executive vice president of MGM Resorts. “Now, it’s a reward.”

Ardent Progressive Systems and Games, which created the Ardent Complimentary Validation System, has installed the technology at the Venetian/Palazzo, Hard Rock Lake Tahoe and Westgate, the old Las Vegas Hilton. Also on the horizon: Golden Nugget, Treasure Island and Hard Rock Las Vegas.

To earn a drink at the bar, guests must play a certain amount of money over a set amount of time. At Caesars, once you reach the minimum level, a discreet green light will flash as a signal for the bartender to start pouring. Broome said that Caesars’s system averages out to $4 a minute, and the light starts blinking after two minutes of play. Each drink is worth about $10 — the value of a Johnny Walker Black or Smirnoff vodka but not a top-shelf malt scotch.

“If you don’t keep up the four dollars per minute,” he said, “it will start flashing red.”

To restore your greenness, you will need to feed the meter.

MGM uses a similar system, with printed vouchers instead of lights. Feldman didn’t provide a specific monetary figure but advised customers to ask the bartender how much money they need play to receive a free drink.

“This isn’t a way of trying to induce further gambling,” he said, but is meant to acknowledge a certain breed of customers.

Before the new arrangement, the bartenders had to monitor the video-poker activity while also concocting cocktails, ringing up tabs and bantering with customers. No surprise that some visitors sipped without paying or playing.

“The green-light program eliminates the guesswork,” Broome said.

Now exposed, the freeloaders can either court Lady Luck at the bar or repair to the casino floor, where the booze still flows freely — at least for now.

Correction: An earlier version stated Ardent Progressive Systems and Games, created the Ardent Complimentary Validation System used at MGM. The system is used at Caesars. The story has been updated.

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