Are coasters one step up from leaving plastic covering on your three piece suite to protect it?
I suppose so! My lovely ILs did this for several years, until the squeaking and crackling every time someone sat down finally did their heads in.
Its funny though isn't it how people's definition of class differs so much. I agree the quiz is pretty crap but some people do indeed feel different if they can afford to them "nice" stuff and there is nothing wrong with that. One person's vulgar is the next person's good taste.
I agree entirely that one person's 'vulgar' is another person's good taste - the thing is, though, that tastes are also partly mandated by their social class, or the social class they want to identify with. I mean, I'm pretty sure that Princess Charlotte, even in her most private and informal moments, never wore a baby headband. 
Cuddles, whether or not social class is something you are aware of in your daily life, it has a continuing enormous impact on people's everyday lives in things like educational attainment, health, life expectancy etc etc.
It's not some minor issue involving what you call the piece of furniture you might slouch on in the evenings when relaxing.