Because of their disgust of libs/Brown,
People are willing to overlook the cop exaggerating and hamming shit up, after he shot someone.
Now, if he shot their grandmother, or shot their dog, they'd look at "I got punched once and thought I would die" as total crap. They would ask why he was close to blackout and didn't call for assistance. They'd press him a little harder on the textbook response on the shoot, which looks anything but based upon his injuries and so far away he killed the dude. 150 is a LONG way to run - no radioing it in... and then to open fire.
And the cop's claims about being helpless and weak - he's been a cop 8 years and he's 6 foot 4 (same height as Brown), and he isn't skinny. And that's 8 years of cop training and hardening. Look it up - in his OWN WORDS, wilson is 6 foot 4.
He's a tall ass dude. Sorry, but if he shot one of our grannies, we might look harder at his "i was just a 5 year old, and he was the Hulk" statement. He's hamming it up to justify the shoot and get pity. Which many accept, as long as he's killing 18 year old idiots.