I've only read about Target & Amazon
I kind of get where they are coming from: it seems that usually, you don't give advantages to only 1 distributor, so this special deal with the Apple store & the ban on preorders for everyone else rubbed them the wrong way.
According to articles online, it's more about sending a signal to Sony (or any other label) that this sort of preferencial treatment won't be accepted without a fight, but I don't think it will dent Beyonce's sales that much... People will get the album somewhere else if they really want it.
I get that but Target are clearly throwing their toys out of the pram because they always gets the bonus tracks and special versions of an album which gives them the advantage. They're just sulking.