They were OBVIOUSLY a yuppie family.
My wife an I raised three daughters, which included twins, and on th rare times when we were able to go out to eat our children were with family members until they were at an age to understand what it meant to be respectful to others.
Babies are not able to understand this, but you would expect that their parents would unless they really could care less and only want what they want when they want it and if means annoying others that’s not their problem.
If these parent can afford this expensive diner they they can afford to hire a baby sitter.