"Creepy" is a natural category - it describes behaviors that are likely to cause a certain emotion. This emotion is triggered by things that are obviously bad, by things that are subtly bad and often announce worse things when the group isn't looking, and by non-bad things.

Our aim is to combat the first two while allowing the last one. Anti-creepy action ("Stop all creepy behavior, get out if you can't") acts against all three. Banning obviously bad things ("Ask before you touch") acts only against the first one.