By having your license plate blocked-out in pictures posted on the internet prevents world-wide law enforcement personnel (worthy or unworthy) who have access to DMV computers from running your plates and finding out who you are and where you live.

Sure; while your vehicle is on the road in public, everyone can view your license plate. That is a very small number of people viewing your license plate and an even smaller pecentage of people who have actual DMV computer access (like a typical policeman in a cruiser), when compared to the entire world on the world-wide-web.

For me, I don't want anybody knowing where I live unless I specifically want them to with my explicit permission. That's why I have my official street address listed as a PMB (Private Mail Box) going to a local commercial MailCenter type business outlet that rent-out a PMB. In this way, I don't care if my license plate is posted on the internet; I'm safe.

It helps me sleep better at night knowing I'm not going to see a black Chevy Suburban or a black Crown Victoria parked across the street from my front door. Plus, it saves me ammunition.