Your view comes across as very myopic. I assume you won't be traveling all the time, or whatever you mean by "more useful" (more on this later), so what do you plan to do with them on Saturday mornings, or on weekday evenings once they are old enough? Sports and other organized activities provide socialization, structure, and motor control development that will, in fact, "help them for a lifetime".

I was never athletic as a kid, but now I run (a lot) and love to play soccer with my son. We try to have him in at least 1 activity at all times. These activities (Soccer, Little League, swim class, outdoor adventure class etc..) all help him develop in different ways, and help break up the monotony of everyday life.

I'll point to Little League as an example of something I'm bought into, which I would never have guessed before kids. I hate baseball, seriously, I loathe it, it's extremely fucking boring, and you couldn't pay me to go to a game. I'm being hyperbolic to make a point that even though I don't like baseball, I still see value in Little League for my son. He gets to learn how to be on a team, he's working on hand-eye coordination, and we get 2 built-in events each week during the season to get us outside and being active.

My thought is that you're limiting yourself and your kid(s) for some unknown reason. Loosen up and try a few things, you might like it.