DaDancePsych, I love your estimate of "I'd probably be the 5th / 10th / 200th person invited..."
I think in most situations, we KNOW where we would probably fall.
I think that's why my DH wasn't insulted to be B-listed that one time. We knew they'd have other people who would naturally fall before us, and they wouldn't have HAD to invite us at all. But they did, and it wasn't an insult to know that there were 80 other people who came before us, because of course they did.
That is a very good point. What is so terrible, really, about not being on the very short list of people who would be invited to a smaller event? We can't be everyone's very best friend. I wouldn't WANT to be in inner circle of everyone I like!
I don't think this is really "B listing," anyway. I think that that term means hosts treating some guests better than others -- like, some guests get a full meal, others are only invited for dessert.
This is more like the "second flight" situation -- where the hosts realize that for some reason (change in venue, infusion of cash, learning that a larger number of invitees than anticipated will be unable to attend, etc.) they will be able to invite more people, so they do. That doesn't mean that they are inviting people they don't care about just to increase their gifts! Not at all. Everyone has some "maybes" on their invitation list that they end up not being able to include. Often, these people are not borderline acquaintances at all -- they may be more like "would love love love to invite but don't have space because of the people on the 'must invite' list."
But it all gets blurred in the Zoom situation. I mean, that father of the bride in the 200 person Zoom wedding told me he figured maybe they would've had 100 at an in-person wedding -- but I don't think he even thought about it until I asked; they hadn't planned and then cancelled an in-person wedding for 100.
So it's more like a couple deciding to have a wedding for 200 in the park with pizza; if they could only have had 50 for a more expensive/smaller venue, does that mean that the other 150 are "B list" or otherwise insulted? Maybe it's a compliment -- "We could've had a fancier reception, but it was more important to us to have more of our family and friends."
Extrapolating to Zoom, I guess you could even say that a Zoom wedding for 30 is nicer than a Zoom wedding for 200 -- you can't see everyone at the same time, etc.; we all know the down sides of very large Zoom events. But they chose a Zoom for 200 anyway so they could include more people. Are 170 "B" guests?
I do think that I would feel different if it were 1000.
I think there is a whole new area of etiquette to be written.