That's the thing, it's usually the "immature" punks in civics or even, yes, Mustangs that don't know what their doing or have a power rush. A 10 second car has no business racing on the streets anyway. I know what you mean, I've seen people trailor their cars to parking lots and street race them, slicks and all. No freakin' way, if they went through that much trouble, Gainsville is only a couple hours a way and they have a trailor, no excuse!
Besides, if I wanted to stay safe all the time I sure wouldn't have bought a Mustang, they aren't the safest cars on the road as you can gather from that story you posted. And a GT500 may be just a little more power than most can handle on the streets. I will say, when I had my old S-Trimmed 95, I tried "dropping the hammer" once on the interstate and lost the rear end a little, never again!!!!
I'm talking a little stop light to stop light or out on an open rural highway type fun. If you're in a place where you can lose control you shouldn't be racing in the first place. And since GT500's are pretty solid with handling capability, the person driving it was full of FAIL! And he paid with his and passengers' lives.
I'm 29 years old and drive a hooptie stang, I was really into street racing back in my Fox days, right after Fast n Furious came out... all these guys and their NOSS, I had to show them what was going on, cost me hundreds in fines, trip to jail for driving on suspended, you name it!