Update - i went ahead and bought 2 copies of GTA V for and it went straight through.
Best buy's website here:
has a promotion for pre-ordering GTA V and getting a free Rockstar game off the list. GTA V for both platforms shows up on the top AND bottom and it lets you add one of each to your cart and shows up as being charged for a single game. I didn't finish the purchase but got through to the payment page and it doesn't seem to notice anything is wrong.
Pretty sure someone screwed up and it may get cancelled but...2 copies of GTA V on release day for the price of one?
For some reason store pickup near me was unavailable at every store, not sure why, but shipping is free.
Oh and of course this carries with it the $10 pre-order RZ cert (probably not for each copy but that'd be crazy).