Food portions and being (or acting) unable to finish all but the daintiest serving sizes definitely has a class component to it, at least in the US. I think this behavior's shifted "down" a notch or so, alongside fitness-as-a-class-marker (see also: athleisure wear) as the upper-middle and more perceptive anxious/striving middle classes have latched onto it. In tech circle's I'd guess it's very common, they consisting largely of those two class groups (using a Fussellian system of classification, here).
Of course our meal serving sizes do probably vary more than in most (saner) countries. On the low end of the dining-out spectrum, one is often served enough food for two or more meals. There's an "if I don't feel stuffed to the point of nigh-immobility, I got ripped off" attitude in that sector of the market.
Of course our meal serving sizes do probably vary more than in most (saner) countries. On the low end of the dining-out spectrum, one is often served enough food for two or more meals. There's an "if I don't feel stuffed to the point of nigh-immobility, I got ripped off" attitude in that sector of the market.