Why lift weights when I could just use a forklift?
At some point someone actually has to do some thinking. It's hard to train your thinking if you just offload every simple task throughout your entire education.
So you're saying you've never used StackOverflow in your life?
I find your analogy works against your point, because manual labor does use a forklift and other heavy machinery whenever possible. It's better for human health (and the backs of blue collar workers) that way. Now the only people lifting weights in gyms are those who choose to be there for their health and not because they're forced to.
At some point someone actually has to do some thinking. It's hard to train your thinking if you just offload every simple task throughout your entire education.