So I immediately asked the person working there what the deal was (wow, that last sentence was a grammar nightmare). He had no idea. So I emailed GW. Nothing. I messaged my FLGS on Facebook. A few days later, I got a message from them saying that essentially, there was no special deal, no free 6th LRB with purchase, no discount on the Black Reach box. The sticker is just there to prompt the salesperson to say "It's still a good deal."
I'm not sure what is worse - this marketing ploy or the fact that they didn't tell store owners until they put the stickers on. I have ALWAYS sided with GW when the Internet started grousing about Finecast, tournaments, price hikes and whatever else because miniatures wargaming is really free market at it's finest, and every event that people complain about is an exemplar of pure capitalism.
But this sticker? Are you kidding me? Poorly executed marketing designed to target newbies and the mentally addled. Dumb.