well... those people have never been in a cam-site where naked 18 years old actually look like 18 years old, hell, even 30 years old still look like 18. Hollywood use "old" people to play teens and young adults, there lies their confusion I guess, either that or they have no recolection on how teenagers really look like when they where young, also they are probably 40 year old virgins and they've never seen a real 18 years old naked or even looked at their faces, lol