Are some white people intimidated by well mannered educated black people?

I live in the south. It's a small town. I am educated and very well spoken. I have an office job do i can - dress nice with jewerly and heels and sundresses. I love smiling. Sometimes i feel like white people in cashier roles or more blue collar roles look at me differently. They get shocked and get really timid. It is almost like they dont know how to take me. Not all of them but some of them. It is like they expect something different. It is very strange...but this is country hickville so maybe it is not too strange. What do you think? Ps. When i drive forty minutes up the road downtown to our metro area the atmosphere feels so different. It is growing and we have cultures and shopping centers in this area.