Why do All the spammers prefer using the groups to spam just after signed up? They mostly create groups which has long meaningless words, with(out) a few pictures in, which seem as if they are created automatically, by a bot. I can't understand this, but they do. Could  a reCaptcha plugin, on the process of creating groups, prevent us from those  spammers? Does anyone work on such a captcha project for elgg groups plugin? or Any idea?