Sorry but I'm not buying the whole watching if you don't have a lapel card. There definitely is an increase in attendants but saying there are more attendants than attendees is complete hyperbole. I find it a little weird that they open the doors for you in the morning and greet most people walking in but it's pretty easy to simile and return a greeting. And, I would imagine they are doing that to see if someone is acting suspiciously. Keep in mind that for RCs, there is a campaign to invite the public. Now, I can't recall a time seeing someone from the public actually come in from an invitation but I guess it's happened. So, it's really hard to say you have to have a badge then turn around and invite the public.
The only time I EVER wore a badge was when I had an assignment and was forced to. Never once have I had anyone say anything to me. Of course, I looked like I belonged in terms of dress, having a bag, etc. But still.....