My point being that you can throw any names on the reservation. I can add sisters, brothers in law, nieces or nephews. None of whom are phantom, but none of whom are confirmed (or even likely) to go.
I'm not sure why you are personalizing a general question. My question wasn’t about you or anyone else in particular, it was a general curiosity about how people can offer to give up “extra” tickets within hours of registration closing. That is a fact, regardless of whether other people intend to use all of their slots or not. No one said you were adding phony guests. No one suggested you (or anyone else in particular) were running up the reservations or hoarding slots, and no one would have been the wiser or cared either way, because what you do is not what we were talking about.
But, at the risk of being repetitive, there are people who clearly have extra tickets shortly after making their MM reservations (as in the same day or within several days) and adding a few random names to a reservation that can easily be modified later is a rather low bar, whether you intend to invite specific folks along or just want a few extra tickets “just in case”. That may not represent your booking habits, but no one ever suggested it was.