Thanks for the encouragement!
I was going to call it a day since I got my $50 GC coming from BB, but decided to give a competitor a shot. I called my local Staples and asked if they accepted competitor coupons. The girl said yes, so I headed over. Picked up a Kindle Paperwhite and had very little issue checking out. The girl I spoke to on the phone rang me up. The manager initially said "this can only be used at Best Buy", but I mentioned I spoke to someone who said I could use it there (I figured it was the girl checking me out, but wasn't 100% until she admitted to saying that). He looked it over for a few seconds, then told her to ring it up as a competitor coupon. He tried scanning it (???) but it didn't go through (obviously), so he just entered in the numbers and took $50 off.
Receipt attached for anyone who it might help.
I'm kind of regretting getting the paperwhite over the Kindle Fire HD. Think its worth the extra $70 for the fire HD?