Do they? I've recently started drawing my own comic*, and I'm doing my own weird style of layouts (sometimes thumbnails, sometimes sketching a bunch of panels I'll need, then figuring out how they'll go together on a page), but I've figured out that one advantage I have over a professional is, I have time to draft. It makes sense, but I wouldn't have thought it'd give a pro much time. (I'm not doing it 9-5 like a pro would, but it can still take weeks to do a single page.)
Do you refer here to the Fear Itself volume? (That's the only one that fits the description, but I think of it as v5 - I imagine you're not counting Omega?)
* I got tired of doing random doodles during meetings at work, and started doing a comic instead. True story.
~ Le Messor
"Forget it. No Civil War picture ever made a nickel."
~ MGM executive, advising against investing in Gone With The Wind