If this doesn't convince one to stay away from crowds...

Remus is proven correct again;

"...As always, observe Ol' Remus's Most Excellent and Inviolable Rule One For Survival: stay away from crowds.." 

Good advice.

BTW, Matt Bracken was prescient on this one.

UPDATE: 10/3/17

Remus sez;

"About the massacre in Las Vegas, Karl Denninger says, at Market-Ticker: 

 The process to obtain a legal machine gun is materially more stringent than the process to become a police officer. What we don't know at this point, of course, is whether said machine gun was legally purchased. It is quite likely that it was not—that it was either illegally converted (in which case all the background checks are worthless) or it was illegally sourced and acquired (in which case all the background checks are also worthless.) 

... For the moment there are no conclusions that can reasonably be reached but that hasn't and won't stop those who wish to both pick your pocket and focus ever-more intrusive measures on people who have done exactly nothing wrong from exploiting this event for their own purposes. 

The best defense against mass murder is to be somewhere else. To repeat Ol' Remus's Most Excellent Rule One:
                                               Stay away from crowds."

 Shocker.