Buying expensive "status symbol" versions of items.
Like clothing. A rich guy buying an outfit for a few grand? Classy. A poor person spending a few grand for a full set of "supreme"? Trashy.
Or cars. A rich guy buying a Porsche? Good call! A poor person whipping a bmw? Stupid and wasteful, it's a more expensive car to purchase and MAINTAIN... for someone who can't afford it. Even sadder when the poor person buys a used Mercedes and then proceeds to clap it out. Sun damaged paint, dents and dings, scratches and a tire that's slightly deflated, brakes that squeal...
Day drinking. Affairs. I could go on. Lots of things are considered broadly acceptable in the upper strata and cause for ostracism with the lower. I know, because I grew up poor, and am now moderately well-off.
Not working