> If you see someone on the street dressed like a middle-class person (say, in clean jeans and a striped shirt), how do you know whether they’re lower middle class or upper middle class?
Nonsense! You don't know anything about someone's economic class based on their appearance.
You can make an educated guess, usually very easily. Not necessarily the clothes, but definitely the shoes, accessories (especially bags, watches, and jewelry), tattoos, and teeth, hair, and skin. Richer people spend more on accessories (and repair their shoes!) and taking care of their bodies, because they can. And it shows.
You can probably make a good guess based on appearance (clothes, race, gender, general appearance) + their location (which if you are looking at them in person, you know). You are right, you can be wrong, but it'd be worth testing, as my gut feel is you'd get more right, than wrong.
Nonsense! You don't know anything about someone's economic class based on their appearance.