Paddock was wearing a suit jacket? Who operates heavy machinery in a jacket?

1. I am wondering about the jacket. It bothers me.
2. Who operates automatic guns in a suit jacket?
3. Wouldn't it be more logical that he was wearing a suit jacket because he was expecting a person to come and visit and he was hiding a handgun?

If I was going to shoot artillery out my hotel window, I don't think I would be wearing a jacket.

Just me I guess.