I grew up in the prairies so backpacking wasn't even a thought for me and my friends. What were we going to do, wander around out in a farmer's field? (Actually, we did do that, quite often) Luckily, I had parents who were big into camping, so while my friends spent their summer's playing baseball in the city I was out camping, fishing, boating, and getting exposure to the great outdoors. Once I moved away from the prairies I had a basic outdoor skill set that easily transferred to backpacking.
Living in the Yukon though, I find that almost everyone I know is into outdoor adventure, whether it be backpacking, canoe tripping, mountain biking, skiing, climbing, hunting, or fishing. It ranges from people doing multi-week expeditions in the backcountry to families just trying to get out for day hikes or overnight camping trips as often as time will allow. In this type of atmosphere, you're more likely to see kids getting involved in sports like xc-skiing and kayaking than joining baseball teams. If we didn't have such easy access to such vast wilderness, I doubt that would be the case.