Originally Posted by Hektore

The bear you saw was a black bear.

It may well have weighed less than you, been shorter than you, and black bears are particularly skittish, they generally flee any loud noise or intimidating display, it's safer that way when you only weight 150 lbs. I have frequently chased bears out of garbage cans near campsites and hunting cabins.

That is not the same thing as a grizzly bear, which is about the same size/weight as a small car. You do not, ever, stand down a grizzly (at least not more than once).