If it weren't for the author, those kids wouldn't have anything to look at and the publishers wouldn't have anything to get rich off.
And if it weren't for the Illustrator the pic book wouldn't exist
And how is an illustrator ever gonna get recognized if never given a chance because god forbid, the author suggested him?
That is why Illustrators send their promo postcards to Art Directors (and often to Editors) at publishing houses. Art Directors look for Illustrators, they find them at SCBWI Conferences, on-line, thru Illustration Agents and from direct mail (the postcards we send them) That's how you get discovered, not thru an Author.
An Author is only one part of the team that goes into creating a pic book. Illustrators are often technically called "Author" because you add a whole other dimension to the story.
Authors are good at writing, it does not mean they can judge art, nor which art works best for their book, any better then anyone else
I know, I've seen art in pic books and have shaken my head too but then I realize not everyone has the same taste in art that I do