Hopefully I think this has changed though. Or I have become grumpy who knows.
Touch panel oven tops is my main hate object in this regard.
Well, everything falls under "unless someone tells you" in the grand scheme of things.
But as far as furniture knowledge goes, it's of the most basic type, not something "just the rich would know".
Some others are very hard to observe yourself (e.g. the poisonous effect of lead) but by now they are embedded into the collective consciousness.
My worry is with things that are neither. In this particular context these are things that you know if you grow up in a rich/middle-class family, but hard to come by if you become rich/middle-class later in life.
Mahogany and teak was in fashion around here for a while and oak went out the door.
Oak was considered cheap so we painted it. The fashion then change to lye treated. Then we went with soap treated oak.
And then one day Ikea came into fashion.
Price is an important function of choice. But we should not discard the fashion trends.
Rich people might have good sense. Or they may have a sense for fashion. But they are still just people like the rest of us.
So the "unless someone tells you" really rings true to me. Rather than equating rich with good and hence equating good sense with common sense - I think it is a really interesting question.
What opportunities and choices are not obvious to us have-nots?
I never believed that that getting rich would make me happy and solve all my problems. But I am quite sure that I would get a nicer set of worries and problems than I have now.
Would I like to experience that for just a day? No, thank you. Ignorance can be a bliss.
It is one of those Schroedingers cat like questions.
That's the point. Most of it is flaunting waste of labor or materials.
Imagine how much labor it took to keep everything white from getting dusty and sooty in the era of coal and wood stoves and lamp and candle light.
It depends on your background. I grew up in Russia in the 90s, back then it was considered cool to put plastic panels on the walls of your apartment. Fresh and modern look, easy to wash, clearly superior to wallpaper. It was called "euro-renovation" as opposed to soviet-style or "grandma" apartments.