Apple prioritise the user at the expense of the developer. I think this is the right balance.
> I cannot install emacs on my Mac.
What's stopping you?
> Software that is free (as in GNU) is charged for in the App store.
I don't think this is in conflict with the spirit of the GNU project? Paying for software distribution is fine in the eyes of the GNU project and their licence. What's your problem with it?
> I am amazed that they care so little for those who are not quite the most important.
Apple think normal users are the most important, not developers. I think they're probably right.