I really wish the NPCs weren't all a bunch of homicidal maniacs. Really, a stable worker is going to go up and start PUNCHING a dragon in the face. Hmm. What's going to be the end result of that one. I hate when dragons attack near cities, it almost always results in the death of an NPC or two. I wish they would RUN INSIDE and let me do my thing. The main thing I'm worried about in every fight is whether or not any NPCs get killed. There's few enough of them as it is!
To be fair (and stretching an "explanation"), most towns dont believe in the dragonborn until they saw him killing a dragon. They even admit that to the player. Although, its true, people should run from a dragon, but, a lot of the npcs are former guards/adventurers so it is logical that they try to defend the town. What isnt very logical is the horses attacking the dragons, animals should run by nature.