Flat Design seems to take its cue from advertising (instead of editorial). Ads (especially in magazines) often look great - clean, elegant - and editorial designers can be envious. But some hoariness is not only functional, but helps offset substance from marketing.

I agree, and I wonder if a lack of hierarchy plays a part - the programmers may not be great at design, but designers would have to tell the programmers what to do. I don't know about others, but I prefer not to be told what to do!