Since Rifle doesn't get up until after noon, my take is that I would wait until he's a little older. Eight seems too young to me, unless he's very developed already.
Plus, as you mention, it's a lot of commitment with lots of travel and games, which could potentially lead to burnout at an early age.
And then there's the F***ing expense involved in it all. I dated a woman back in the 2000's that had a daughter that did travel volleyball, and every damn weekend, they were off to some location in the Midwest to play, and stay in hotels for the weekend. I guess if you can afford to spend your money for the betterment of the kid, it's fine. I was more distressed over not getting the opportunity to get some nookie during travel weekends.