I know you're rant is in jest, but I want to respond to this anyway.
You don't understand advertising. The ads you see in gunrags and on Web sites are more branding tools than "sales" tools. They reinforce the image that the company is dependable, reliable, etc.
Their secondary goal is to promote the benefits of the weapon and what sets it apart from the competition. If there is no competition and this is truely a new project, it serves to educate how the product works.
Finally - adveritising, marketing and sales are not exact sciences. The best campaign in the world can be built around a lemon and basically waste the company's money. Alternatively, some people understanding that said product is a lemon may turn the product into a "cult" status item. There are plenty of people who purchase things, ironicaly, not because they are great but because they are fringe, oddball items.
A campaign is usually drafted one to three years before product release, with ads debuting 3-6 months before product release. Ads are then flighted differently depending on how you want to sell the product (is it something seasonal like a hunting rifle, or "ever-green" like a self defense pistol?).
To answer your question of "why do they keep advertising when they cannot fulfill demand?" - Because you want to keep demand high. For every person waiting on a list to get said product, there are two or three people who haven't even heard of the product. Not to mention that you buy ad space very, very far in advance (and usually in bulk to keep cost per unit down).
Now that my rant is over, let me say that it might be a regional issue - at the last gunshow I was at I saw six different Ruger Takedowns, all reasonably priced. Plus, look at it on the bright side - having a hard time finding a weapon is a good thing.That means more people are entering the sport.
But I sympathize - I was shopping last night and couldnt find two different guns that I had decided I wanted to buy myself for Christmas.
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