I downvoted your original comment as well, though I will admit that I was somewhat conflicted in doing so. My reasoning is that the crux of your argument is based on the statement you just made -- "It's as if they think their customers are dupes," -- and I think that's a strawman.
It's common knowledge that companies offer sales to move product. It's also common knowledge that is a benefit to the companies. My opinion is that affect does not, or should not discount the news of the sale. It's like critiquing a television ad for being self-interested. Of course it is, it's an advertisement, as this is. That doesn't mean that we should dismiss it any more than we should dismiss any product that has a price attached (unless that's the point you're arguing -- I don't mean to rule out an RMS-style argument here).
For what it's worth, they are losing millions of dollars on this deal. You're right, it's a loss-leader, but they are losing revenue by offering the sale. That's how a sale works. You offer a discount to get people in the door and hope that the quality of your product can sway them into becoming loyal customers. If they are unable to convert those prospects into customers because their products aren't strong, then they will have simply lost the revenues otherwise entitled to them had they not offered this sale.
In summary, you took the obvious point and made it sound much more negative than it is. On a more meta tangent, I recently posted something like "Now that I know what a middlebrow dismissal is, I'm worried that every dismissal I make will be categorized as one." -- I made that as a joke, but I'm honestly concerned about it and now that I'm aware of it, I believe that it is a problem on HN. I believe there are numerous problems on HN, and through downvoting, comments and my own behavior, I would much prefer it be fixed than abandoned. My personal fix against the middlebrow dismissal is to not be dismissive, which happens to fall under my own personal HN guideline of "assume good faith."
By 'assuming good faith' of all parties and not being dismissive without being constructive, I think we'd have a much better environment, though I do worry that it would become too 'vanilla' (as my own posts often tend to be when I reread them.) Regardless, the easy fix for you at the moment is to just quit caring about karma altogether, and then you can probably ignore these meta-discussions outright.