I think it depends on where most of the people live.
Miss Manners was ranting about this stuff thirty years ago, saying things like, "Only those people whose names are on the invitation are invited," and "Either accept the invitation as-is or promptly and politely decline."
“... ranting about this stuff thirty years ago...”
Yup. I swear as I get older, I think the “older” rules make so much darn sense. For example, ONLY the bride wears white. The last two weddings I have gone to had some attendees wearing white (and yes.. the bride was a bit miffed). The invitation read “as is”... thus, “and family” meant the kids WERE invited. No “and family” meant the man or woman only. “And guest” meant the person was single and could bring a date. The absolutely most ridiculous “new” thing to me is several wedding gowns. One for the ceremony, one for the reception and one for “going away”. Sheesh.... pick ONE. Everyone else can make up their mind. :)