You mean all those primary school children forced to lug huge bags on their backs to and from school. Their parents must be idiots. Worse still with high school kids. I feel sorry for them all bending over with these ridiculous loads of books forcing them to crouch when walking instead of walking upright. Interesting case for class action (pun-geddit!)
And if one talks to an Osteopath, Chiropractor, or Orthopedic specialist, they'll as agree that kids lugging heavy bags, year in, year out, throughout school, is exceptionally bad for their backs.
That we oldies did it is irrelevant, those who go through life without back trouble are lucky. Try the flip side.