Trend alert: Both Vanna White and “Seinfeld’s” “Soup Nazi” actor made celebrity appearances for Vegas slot machines on Tuesday.

At the Global Gaming Expo, Mayor Carolyn Goodman presented a key to the city to White on the 20th anniversary of the ubiquitous “Wheel of Fortune” slots, which have taken in $3 billion and paid out 1,000 millionaire jackpots, says slot maker IGT.

Meanwhile, actor Larry “Soup Nazi” Thomas did the “ta-da” reveal for new “Seinfeld” slots at the Scientific Games booth in the Global Gaming Expo.

For years, the Strip has launched slot machines with slight celebrity appearances, but this marketing plan seems to be ramping up lately.

“Party girl”/actress Tara Reid helped get press for TMZ’s interactive slots at the Hard Rock Hotel on Aug. 29.

If stars do red carpets at nightclubs and restaurant events, why couldn’t the next place red carpets roll out regularly be casino floor slot machines?