Having worked for Scribner I can tell you that is not at all how it works. In a nutsehll...
Art is commissioned, the in-house designers work hard coming up with a design, that design gets yays and nays from a lot of different people (including booksellers) and ultimately (Ms. Mod correct me if I am wrong) SK gets final approval.
"It does seem fairly lazy and uninspired to go with such a similar copycat look. Like King can't sell enough books unless the unwashed masses recognize a standard brand of King covers. Here is probably what the marketing guys expect our reaction to be: Saddle up the mule. That lookie like a Stephen King book. I buys it."
Like it or not, SK is a "brand" and there needs to be a consistency with the covers so when people are bombarded with the myriad book covers in a bookstore or online, something must be instantly recognizable to the customer.
Lastly, as someone who has worked in marketing for many years, I find your snarky comments kind of rude.