Racism in Utah Makes No Sense

I was enjoying the show until the nonsense racism scene in Utah. Here is how it played out:
Two black guys enter diner full of white people in 1962. They act very very strange, meek and afraid - very poor acting or direction. They go to counter.
Two white customers, who appear to know the cook/owner, call for him and make comments about the two blacks and smell, etc. Say they cannot eat with them in the diner.
The cook/owner comes out with a butcher knife, asks what the black guys want, one guy orders two BLTs and coffee. The cook/owner lays down the butcher knife and says I can get coffee and does.
In the meantime, the two complaining guys split but can be seen outside through the large glass windows across the street by a pickup.

The cook/owner spits a big goober in the coffee and offers it up.

About this time, one of the two 'Complainers' approaches the window from outside with a shotgun.

White boy warns and runs at / grabs black guy to save life.

Complainer shoots shotgun twice, blowing out two windows. Glass all over and all white customers totally freaked out.

Now think about this. The 'Complainers' live in the town, know the cook/owner and by extention, at least, care more about the white people than the two black guys based on the story. But the complainer shoots into the diner, endangering every person in there, including the cook/owner, and causing major damage to the cook/owners property.

I was alive in 1962. Nobody did anything that stupid that I ever heard of or read about. If the complainers really were that racist, they would just wait outside and shoot the black guys where no witnesses were, or follow them somewhere. Why would they shoot into a crowded diner full of white people with an inaccurate weapon like a shotgun?

I guess my point is, there were real incidents of poor treatment of black people back then, why make it unbelievable like this scene? Someone who was not alive then and has half a brain knows this scene is nonsense, when you distort the past you make it easier for people to deny anything happened. It reminds me of all the shows about Hitler, making up nonsense about him, when the truth is bad enough, same as with Saddam or Bin Laden or Obama. Tell the truth, do not make stuff up.

I have noticed Spielberg does this a lot, blows things up and exaggerates to make a point. I think he is wrong to do this. Especially because of how bad his race, the Jews, treated black people back then. I am from Chicago, every slum lord I ever saw in the 1960's was a Jew. Maybe Speilberg has some guilt and makes non-jews [Mormons in Utah] look bad to take the heat off his people.