I'm not fond of the "fierita" looks, yet I do not judge the book by its cover.
Consider all the people that have ever screwed you and you'll notice that they mostly looked exactly like you. Otherwise you wouldn't have let them close, approach you or let your guard down. Friends, acquantances, bosses, employees, clerks, etc. The facts prove that you've been screwed over and over again by people that looked quite ok to your senses. The hooded thugh is a stereotype hardly ever encountered in the real world, don't worry about him, worry about those you can see without "seing" them. The bad guy usually looks just like one of us. No wolfes and lambs, all the same.
Awareness is a subtle skill that can developped. Unfortunatelly most of us carry our worries around and tune out of our surroindings while in transit. That's when the predators strike.