I've loved football since I could walk, but my dad wouldn't let me play until junior high. He told me that the coaches before then will just teach you bad habits and the injury risk isn't worth the marginal headstart on football skills. I played soccer and baseball instead until I was in 7th grade, then switched to football and baseball. I was pretty good at whatever sport I tried, so I can't say for certain that the parent imposed delay was good for me, but I was an honorable mention all-state offensive lineman in Pennsylvania by my junior year of HS and second team all-state my senior year. There's really no reason for kids under the age of 12 to be playing tackle football, but in my opinion, by junior high the kids should be developed enough to be tackling. You're right though, it is a shame when coaches just use their best athlete as a work horse in any football level below high school.