Last I checked people who are arrested for statuary rape are rarely sold out by the person they have sex with lol. We're sending the message that:
A) People who are under the age of consent cannot legally make the decision to have sex, thus if they're with someone older than them, that older person is taking advantage of their underdeveloped mind.
B) But if you're both under aged it's cool, because two people who are the same age (who both have underdeveloped minds) can't possible take advantage of each other. Nothing could possibly go wrong with two people performing an act that could forever change their lives, especially when we consider them at an age where they aren't old enough to make their own decisions.
Logic that is so warped, the only reason it exists is because people are too afraid of being against it because they instantly are given the social stigma of being a pedophile or being cool with pedophilia (cause remember, to most people all encounters with those under 18 IS pedophilia).
Or, it exists because people think those under 18 should have the freedom to make these choices themselves....while also not considering them legally old enough to make said choices to being with.
Feel free to point out how any of this makes any sense at all.