Gender Roles

I may get dinged for being a sexist for making this observation, but them's the breaks. Why is it that the people who clean hotel rooms are always women, and the people who clean cars are always men? There are exceptions, like high school car wash/fund raisers, but other than that I don't think I have ever encountered one. Is it because women are more comfortable with buildings, and men are more comfortable with cars? Or is it something else entirely and I am just missing it?