Did Fox really have the power to have old DVD stock pulled from store shelves ahead of the first Blu Ray release? I did notice they suddenly vanished in at least one local store at the time, but can’t discount the possibility someone was buying them up to flip on Ebay.

A lot of sealed fullscreen copies turn up for sale with the UPC slashed and covered by a sticker, indicating they were given away to some charity.
http://www.ebay.com/itm/Star-Wars-A-New-Hope-2006-Limited-Edition-Full-Screen-2-Disc-DVD-Sealed-/282408001794