My RB Cody preferred women. He wasn't abused or unsocialized to men, so I have no clue. I think, maybe it's odor or voice or size. Mz Logan likes everyone basically. She'll menacingly bark if a guy (repairman, my uncles) walk in, but after a few minutes, she's fine. I never understood the stories of racial differential in dogs. Cody and Logan never cared if people were purple.