I think discrimination implied intent, though. I'm sure that Scholastic wasn't thinking of Shabbos when they released on Saturday. They were thinking of getting the largest possible weekend audience. And B&N was only thinking, "We're got tens of tens of people begging for this book. We can't keep these books on hold any longer."

I don't think they're guilty of discrimination any more than the corner McDonald's is guilty of discrimination for not ridding their menu of pork, milk, and getting a hectsher.