They have now seen that there are enough who are trained to believe that more MP are better and will put their money down for bragging rights.
You're basically telling me I'm an idiot because I feel I have a use for 36MP. I don't appreciate that. Choose your words more carefully.
What you really mean is YOU don't think one needs so many MP. Now that's another matter entirely. That's just YOUR little opinion.
Actually, I didn't read it that way at all.
Maybe it is my Product Development Manager way of thinking, but Need and Want are two very different market segments. The need is the foundation and creates the opportunity, and in some ways may be guaranteed sales. The want can be fickle and are opportunistic sales, but can make a product a viable proposition. I see dozens of fantastic ideas cross my desk on a regular basis, most of which there is a real market need, but sadly unless they can be sold in sufficient quantities they are not commercially viable on a return on investment and/or opportunity cost basis. So where do the extra sales volumes to make it viable come from - those that want it, either through Marketing (for cameras the big sales message is often megapixels because to Joe Public this is a measureable quantity, after that it can just be techno-babble) or other means (peer pressure?). Not everyone that buys a pro camera is a professional photographer.
As we saw in the leadup to and just after the release of the 5D3 spec lists, many indicated they needed a high megapixel camera (some studio and landscape photographers). What the D800 sales is showing is a substantial market that also want it, and together both could be sufficient to guarantee the investment by Canon.
So as Mt Spokane Photography also said, but was omitted from your quote so it loses some context,
Canon will do it because it sells.
You and others (sometimes myself) may be in the Need category, but it is likely the Wants that will deliver the product for you. I wouldn't take it personally.