I am a mother who swore no guns. But that changed, and I ended up buying a five-year-old Henry a toy arsenal when I surrendered to the fact that my disdain for guns and violence was not his.
Here’s a shocker. Boys are different than girls. And don’t let anyone tell you otherwise.
Both of my boys came out of the womb making blow-up noises and shooting me with their fingers, bananas, toast, sticks, you name it. They also came out loving and cuddly and sweet. Loving and full-body slamming are not mutually exclusive.
Embrace their spirit. Channel it for good. Help them become the protectors and warriors they are meant to be.
This is a great piece by Msgr. Charles Pope. Watch the video.
Five Halos 
That is one thing I never got about modern thought, what is so wrong with gender roles? Guys can be masculine. Women can be feminine. Neither of those terms are bad words and they are NOT synonymous. I really do think that when society tries to make the to sexes equal (not equitable) they are doing a disservice to all.
That does not exclude the fact that girls/women can have some characteristics of a more masculine POV but they should not sacrifice their femininity to it. Let a girl be a girl. And a boy be a boy. If God did not want us to be different, He would have made us androgynous beings. Thank Him that He did not.
And you are right, it is not so much that the boys like to play warrior games that is bad. It’s more to be sure that the affinity for things like that is channeled in the right direction so as to form them into sons of God.