The same reason a general contractor makes more than the carpenter he subs out? Or the same reason the real estate developer makes more than the architect?
It is mostly a question of making decisions that "scale".
If engineers are mostly deciding "how to build" something, then managers are mostly deciding "what to build".
Assuming managers are not just "schedule keepers", and are actually making decisions, then it makes sense for them to be paid more based on making those decisions correctly.
If the managers decisions on "what to build" are correct, and 12 months down the line a product is more successful because of that decision, their compensation can be much more than that of individual engineers.
Certainly there is much overlap between "what to build" and "how to build it", but in general it is the "business" role to decide what to build, and engineerings role to decide how to build it.
The Socratic method is one of the most annoying things ever, not the kind of thing that will be accepted by equals. It is a poor method of information/knowledge transfer, and thus wastes the time of the person looking for info while prolonging the period in which they are asking for something. It is close to a perfect example of claiming higher status than another. None of this calculation is normally said or even thought, but it is felt. People who appreciate the Socratic method, done well, are a small minority, and it is usually done badly.
You come off both condescending and lazy when using the Socratic method with peers. Either clearly state your positions or take the downvotes.
Socratic method works in a student-teacher relation. By using it here on the message board you immediately assert that you know the true answer while the rest of us only know ignorance.
You're not making any real arguments in any of your posts (except the grandparent to this one), in my opinion. When confronted with the assertion "X", responding with "does anyone else feel not-X?" or "the same reason Y?" strike me as lazy rhetorical cheats to assert your opinion while trying to avoid just laying out an argument for it.
As such, people seem to be downvoting them as noise.
I think they shouldn't (upvoted all of them for balance) the analogy is valid and ought to be obviously so. Programming is not the only industry where the best "craftsmen" often make less than the "middlemen", that's a very common pattern.