If they know that the gallinoansera clade had already emerged before the K-T extinction, they most likely also know about birds being dinosaurs. Specifying "non-avian" everytime is a pain and saying "K-T extinction" is not understood by all, no need to correct them for semantics when their wording gets the point across.
Have you not been reading this thread? Dinosaurs never went extinct. A sparrow is descended from the great raptors
If they know that the gallinoansera clade had already emerged before the K-T extinction, they most likely also know about birds being dinosaurs. Specifying "non-avian" everytime is a pain and saying "K-T extinction" is not understood by all, no need to correct them for semantics when their wording gets the point across.