A few years ago, during Hurricane Rita, some hoodlums thought it would be a good idea to enter the only restaurant still open in a Southeast Texas city, brandishing pistols, and rob the place and its patrons. Turns out the place was open because the law enforcement folks had gathered there as sort of an impromptu "HQ" and rally point. The parking lot was full of LEO vehicles, from the city, county and state agencies. Our brave hoodlums apparently failed basic math as far back as kindergarten, and walked in with guns drawn, demanding money. Let's just say things didn't turn out as they'd planned.
The point is, you can't rely on a criminal to be even marginally reasonable or insightful, so why NOT protect yourself? Sure, it may not come up, but given the critical thinking ability of some people, what could it hurt?