<p>If I had to guess, I'd say it's because there isn't always someone watching the footage. The Machine and Samaritan have it easy, they see everything, all the time, we, petty humans, don't have that capability. And never forget that Reese used to be an international spy so he has a ninja-like set of skills. </p><p>Hope this helped. </p>

<p>I've actually speculated on this before. I mean, wouldn't it seem ordinary for police to pull camera footage from one of the cameras at a murder or shooting scene? I like to think that our Machine has kept Reese safe for all this time as it is still doing even now. Just my thoughts. </p>