Looking for phrase or word to describe when people think things are high class but they actually are not

Question

I feel like I see this often, people attach certain items to their ideal of high class or posh, even if those things are not. I have worked in some fine dining restaurants and its equal parts amusing and frustrating when someone excitedly asks if there is shrimp or steak on the menu, as those things are their pinnacle of fancy in their own minds but in reality can be found at any dirty diner down the street.

Also would be interested to know if there is a word for a low class person who attains specific things and tries to live the high class life through them when the rest of their lives clearly is not. For example, somebody who cant pay their bills because they have to drive a BMW to their job at McDonalds.

Nobody is perfect and I think many people do things like this from time to time, I was just curious if there are specific words or phrases to describe this. Thanks!

Answer 1

A Nickel Millionaire describes your BMW driving rube, Urban Dictionary calls it a "30K Millionaire"

"Klassy with a capital K!" is my favorite for your uncultured restaurant patron or just "Gauche" is the old standby.

Answer 2

You could say your customer is unsophisticated, as they are likely inexperienced to fine dining (although they are clearly eager to try).

:not worldly-wise :lacking social or economic sophistication
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Your BMW driver also lacks sophistication, but I would likely describe such a person as pretentious.

Use the adjective pretentious as a way to criticize people who try to act like they are more important or knowledgeable than they really are.
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Answer 3

Nouveau riche is the one I have always used in that context. The plural is nouveaux riche.

Nouveau-riche

A big diamond necklace is nouveau riche, really. People who have wealth a long time don't wear such things. - Elsa Peretti

Elsa Peretti