Are we right that the wedding plan is bonkers?

DEAR MISS MANNERS: We’ve been friends with a couple for over 20 years. Our son grew up with theirs — elementary through high school, after-school sports, etc.

Their son is getting married out of town. It’s drivable for us, but would mean a flight and hotel for our son and his wife.

Our friends just informed us that while we are invited, our son and his wife are not, “due to cost.”

Our son will be hurt knowing that we, who are capable of giving a generous gift, are invited, but he and his wife, who are scraping by (he is in school and she is teaching), are not. They would have spent their “gifting” money on expenses for attending the wedding — had they been invited.