lph, it sounds like we have gone through the same thing - I tried so hard to limit my son's exposure to 'war-like' toys, tv and activities, however, you could go for a walk in the park and he would pick up a stick and he and his friends would be playing 'cops and robbers', pretending it was a gun. Are they hard-wired? Probably the same on the girls side. I grew up with my barbies, loved them, and I don't think it did any harm. To echo Tulip's sentiment, when the parents disapprove of an activity, it can often come off as disapproval of the child. It say let her be.
Get on your bikes and ride!
'Bicycle Race' -Queen