The OP doesn't state that people don't call things they can afford immoral. Only that people do call things they can't afford immoral.
(Small typo: "anything like p > .05" should be "anything like p < .05".)
Sorry if this is the wrong place to put this, and also sorry if it's been asked before (three different search engines gave me nothing on this) - but in chapter 7, we see interesting behaviour from Ron's owl: "The owl gave Harry an oddly measured and courteous hoot (actually more of an eehhhhh sound, which surprised Harry)."
How likely do we think it is that Ron's owl is an Animagus? We know that the pet rat which Bill killed in chapter 29 was just a rat; we also know Pettigrew's Animagus form was really a rat; is it possible that Pettigrew had two forms (owl and rat) and abandoned one of them in order to stay undercover? Or, more likely, the owl is a different witch/wizard who is undercover in the Weasley family.
(This feels to me like a "grasping at straws" kind of thought, but EY is indeed ingenious and wily, and something definitely rings not quite true about the pet rat story…)