Except people who get upset about $20 like this will probably do this repeatedly in the future. Is it worth the company's time, money, and effort to support someone who feels entitled to discounts and bonuses, just because other companies do it? If he ends up wasting hours of their time over the course of his buying stuff from them, while they run around trying to make him happy, they lose money on him by wasting time. They also lose out on profit each time they bother to give him a discount or free bonus item.
My company is in a service-oriented market, and we spend 80% of our time dealing with the bottom 20% of our customers and their whining about products, haggling on pricing, and pestering for free technical support (because "It's just once or twice a year!"). Imagine if we were able to use that other 80% of our time to focus on the customers that really do make us money!
You can make the case that they're losing out on his business. But they're really only missing out on hardship and financial loss from an entitled, selfish customer. Sounds to me like NB wins on this one.
I agree with the others. OP, you're not entitled to the
gift card. You didn't buy during the promo. It's as simple as that. You asked if they would honor the promo anyway, and they said no. Why get so upset over $20? Obviously the $20 doesn't mean that much in the long run. If you're so broke that it does matter, why are you burning so much cash on an expensive burner, when something 1/3 of the price can do the job, too? Just let it go and enjoy the awesomeness that is the Blichmann Burner.
(Just ordered one, myself! Can't wait to try it out!!)