"The argument that "boys will be boys" actually carries the profoundly anti-male implication that we should expect bad behavior from boys and men. The assumption is that they are somehow not capable of acting appropriately, or treating girls and women with respect." -Jackson Katz #feminism
This is rape culture, sold to us by every media form since the Bible. (yes, I'm sure you could cite even earlier yet that book is the "moral guidepost" that makes this so easily ingrained from babyhood.) It's a violent, ridiculous, false moral, construct.