What happened to those Flutheronians (AKA Jellies_) who join and are never heard from again?

You see on the leader board that chatchman103, fhttnk, fatguitartman, maryaccounting, etc, joined the collective X nanoseconds, or X minutes ago. Some of them even pick up a follower, then you never hear from them again or see them. Does that mean everyone who seemingly joined and then appeared to abducted by aliens were not real people but robots or some business spammers?