A) If those customers want to be with their families for T-giving then why are they flying on T-giving day? Answer: so few are flying on T-giving day that the term "all those customers" has very little impact. Perhaps better: "Did you consider those few unhappy customers who won't...."

B) US isn't canceling these flights because they "don't feel like flying" they are canceling them, most likely, because they are unprofitable.