In rural America where both (or all) adults work and the apartment they rent doesn't have a dishwashing machine: buying paper plates, keeping them in stock, and eating from them on a regular basis is not
at all an uncommon occurrence in the US. Do you think stores would have such huge sections entirely devoted to disposable eatery, cutlery, bakeware, etc... if they were only being used for picnics?
I'll let others debate the wastefulness issue. It has nothing to do with whether or not it's common practice.