Another Moto X Post - what it means for carriers

Ok so we all know the moto x is coming and will be "The first smartphone you can design yourself." With that in mind, how would this affect carriers? We don't know the exact details that motorola will let you customize, but how does this affect in store purchases? How many different colors/different options will carriers have to stock in their stores just so that someone can come in and say "i want a red moto x with 32 gb of storage and .....( any other customizations). perhaps you would have to order the phone online. Now if they want this to be a success, they can't charge $600 online for a phone, even if it does compete with the likes of the gs4 and htc one because very few would be willing to pay that outright. Maybe carriers will only carry basic options? What do you guys think this customization idea means for the carriers and the way we purchase our phones in the future?

On a different note, maybe to combat this issue, maybe the phone will just have something dumb like interchangeable face plates...that would be the biggest disappointment of all time.