I don't have the source now, and I may be mistaken. I thought I remembered reading somewhere that InDesign's creators drew significant inspiration from Tex/LaTeX, but I can no longer find the original source. Perhaps I was thinking about QuarkXPress. I did not mean to imply it was a direct derivative. InDesign was openly created to compete with Quark, so its feature set was much more in line with Quark than with Tex.
I completely agree that LaTeX is not ideal for designing magazines (although it's used by some academic journals), and its support for cover layout could be better (indeed, it took me longer than it should have to create a fairly simple book cover with Latex just last week).
But as a typesetting system, it's great, and works great for books.