This is just an anecdote, but today I got to a room that was too
crowded (I was late because of another obligation). Unwilling to
crawl over people, since I was the late one, I went back into the
hall. In previous meetings I used meetecho to follow along in this
case, but since I hadn't registered it was a little troublesome. I
just used the audio, and it's no big deal, but it might be a useful
illustration of one bit of friction that comes because of the remote
registration thing (unless everyone registered on-site automatically
gets a remote registration too, maybe conveniently printed on the
badge or something).
Note that I am _not_ saying this proves anything about whether
registration is a good or bad idea or whatever. I only mention it as
another anecdote (and of course, in one sense the plural of "anecdote"
is too "data").