@Ifeelsuchafool, but that’s a fairly classic class distinction — novels from the early 20thc set in aristocratic houses often feature parents registering with impatience the fact that the governess has taught their children ‘polite’ lower-middle-class table manners, to say ‘pardon’ etc. (That’s partly why they got sent off to board, to teach them ‘better’ manners!)
(The one I can think of offhand is MJ Farrell’s Full House, set in an Anglo-Irish Big House, where the governess tries vainly to instill her idea of good manners in the young son of the house, while her aristocratic employers ‘eat vast quantities of very good food in a careless manner’., and think they need to get rid of her as she’s so useless.)
Not suggesting your dd’s classmates were the aristocrats in this scenario, but notions of what constitutes ‘good manners’ aren’t universal.
And I don’t think your point about the family your daughter charred for is in any way surprising. Further up the social scale doesn’t imply ‘cleaner or more hygienic’.
I eventually stopped visiting one university friend’s parents (minor aristocracy, ‘small’ Palladian house in Berkshire) for weekends, because although I was vegetarian and just semi-starved or ate peanuts in my room because they lived on meat, especially game, and starches, the friends I used to visit with would almost always get stomach upsets — investigation showed that the friend’s parents would cook a joint, and just leave it out, uncovered, in a warm kitchen for days, often subsequently cooking another joint and leaving that out, too, and using the ‘older’ one for lunchtime sandwiches, or reheating it etc. Concentric rings of meat developed. Friends concluded you were safest with the one closest to the Aga, as ‘newest’.
(Dishes ‘washed up’ by the dogs didn’t always actually get washed by a human, either.)
Anyone finding either of these things objectionable would have been considered rather prissy and non-U.
Which is a lengthy way to say that ‘higher-born’ does not imply what other people might consider as having good table manner or being clean!