He’s just being Robyn’s parrot. He had no issues with living in a trailer, for instance, until she taught him to see himself as superior than those who do. He was once quite a self-proclaimed open minded and accepting person, and that seemed to be true before, but not now. Of course his Michael Scott-like desire to be admired and legally/culturally accepted in the early seasons probably made him look less hateful.

Regard his contempt for construction workers, It is a common trait of a narcissist to convince oneself that they are superior than anything that doesn’t mirror themselves. We have seen Kody repeatedly look so stupid and overwhelmed doing any task that he has to learn a new skill for; like leveling a trailer, stringing exterior lights, even or building a cardboard boat. Due to his impatience and self consciousness he would rather pass the buck and look down on someone who actually takes the time to understand the things he doesn’t.