That's not true.. They like to be rubbed where they cant reach them selves.. They do have Scent Glans but that is not the reason they like it.. They don't need there scent on you to Feel safe.. They know your Scent and that it self is what makes them Feel safe..
Cats love being rubbed on the face, specifically the cheeks, chin, and forehead, because that is where their scent glands are, and you are rubbing their scent all over you A., and B. you are cleaning them of their scent... so while they feel safe from predators, they also feel comfortable with you since you smell like them. Cats are heavily territorial, and this is heaven for them.