Well it may have also been due to the fact that Kirito hid his status as a high level player and beta tester multiple times. People don't like dishonesty. Again, not sure what world you are living in where people don't react in such irrational and stupid ways. It's easy to sit there and monday morning quarter back, but until put into a situation like that you can't be sure how you or anyone else would react. A lot people are going to space out and panic, freeze up, etc. It's also easy for people irrational people to group up and reinforce people's beliefs, not to mention it gives them a scapegoat.
Anyway, later on, it becomes accepted to just let the elite players handle this while the noobs stay on the sidelines. That whole thing with beta testers was pretty much just early on, until things settled in.