Quite a lot of people do not know restaurant dishes by their proper names. If you invent a name for your menu item, or use an existing name not common in the vernacular, you avoid most psychological associations with those words. You can describe a Reuben without ever using the words "sandwich", "meat", or "bread", for instance.

Reuben: corned beef, sauerkraut, Swiss cheese, and Russian dressing on rye; lightly toasted

You can even avoid saying "beef", "cheese", or "dressing".

Reuben: cured brisket, sauerkraut, Emmentaler, and Thousand Island on marbled rye; lightly toasted

"Reuben" is not a replacement for "sandwich". That's what it is, after all. But for this particular menu item, no one ever reads the word "sandwich", nor are they likely to say it when ordering. And when that word is not present, people are less likely to associate the restaurant dish with the thing they can almost certainly make at home at lower cost. That's the whole point. You're trying to avoid activating certain areas of the human brain that tend to rein in impulses and encourage activation of areas that stimulate reward-seeking behaviors.

It isn't rocket science, but it is a science. People get paid to experiment on how to encourage people to spend more money in retail stores, and the results they get are often significant enough to sell to businesses. Once you can see these particular fnords, you notice them everywhere. It's one of the reasons why I can hardly stand eating in casual dining chain restaurants any more: I see puppet strings attached to everything, from the moment I see the building to the second I leave.