You know, I think most of us are actually talking past each other here -- I think we really agree.
Because I think that those of us who are in the who-cares-call-it-a-wedding camp are NOT picturing a second wedding after there has already been a small one. I completely agree about that. (I don't even like "vow renewals" and especially not "reenactments.") I think we are all (anyway, I am) thinking of the few-days-before-quick-trip-to-the-courthouse-for-some-technical-reason, such as in a country where a religious ceremony must be done separately or for some equivalent reason in the US. Like, you are having an out of state cousin who is clergy come in and do your wedding, but there is a glitch of some kind in getting the temporary permission to perform a wedding, or they won't be in town in time to do some sort of paperwork, so you run to City Hall some time in the few days before or after the wedding.
And I am also thinking of my LGBT friends who live in states that don't yet recognize same-sex marriage. Their trip to another state for a civilly legal marriage may be more than those few days, perhaps even several weeks before or after their wedding, but I still see no reason to say that they shouldn't still call it their wedding and take their vows as usual. That is just mean, IMO.
In neither of those cases do I feel that the couple is "lying" about anything to their guests. There's just a short gap between what makes them married and what makes the marriage recognized by the state. (Technically, that always happens anyway, because the officiant has to mail in the certificate. So the guests are never really seeing the whole "moment.")
And in neither of these cases, when I've been a guest at both, did the couple either lie about it or make a particular point of announcing the situation, much less alter their vows. Sometimes it just isn't important enough to mention, as in the City Hall example above, and sometimes, as in the GLBT wedding, everyone knows anyway.
For those of you, if any, who think that even couples in these situations still shouldn't say "wedding" and must say something like "We did," what happens if the wedding is first and then the legal proceeding? What are they supposed to call it then, a "preeneactment" at which they say "We will"? And what do they say at City Hall? The government will NOT consider the earlier, unlicensed wedding to be a marriage -- they won't want to hear "We did." So it seems that this only works one way, and what is really being said is that no matter which comes first, the legal proceeding is elevated to the ONLY significant one. And that I just disagree with.