It’s not just “promoting” - the crew especially those serving J should be educated properly not only in the wine themselves, but also how to handle wines properly. I’ve had lukewarm champagne and room temperature white wine served to me before, which I rejected and asked for them to be chilled properly before serving. One of them even suggested, perhaps it’ll cool faster with an ice cube in it?
Other crew would pronounce “chirash” or merlot with a hard T, and had no idea what a “sav blanc” is.