I believe this to be one of life's most important lessons. When you assume something, anything, about anybody, you're also in danger of passing on some kind of judgement, which is also a faux pas in my eyes.
Case in point: last year I worked at a high end department store, the type that many people don't even want to go into because they think the staff are snobby and everything is overpriced. When I first got the job, I was asked many times how people perceive me, how I act when I first meet people, because they were trying to change the image they have acquired and were looking for staff who could look beyond appearances and still be friendly and approachable. Fat chance.
In a competitive commission-based work environment I quickly learned that the staff judged everybody - from shoppers to fellow employees. A peer who became a good friend quickly taught me how to tell "if someone had money" by checking out their watch, their shoes, their clothes, their hair - etc. He taught me how to spot the "fake ballers" who used fake credit cards (while wearing Gucci shoes no less) to the "really really rich" people who purchased modest-looking yet highly expensive goods - Prada loafers, Hermes belts, Ralph Lauren Black Label - things the average person might not notice as 'brand names', but we, as gold-diggers sellers of these goods, notice and we know that these are the big spenders.
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