I agree with this but also see the other side. On a more practical point; if you can afford the SD card, you can afford the CFE card.
I can only speak for myself (though I'd expect this is not uncommon), but I have SD cards already. If I bought a new camera, and was pushing the budget, I'd use those until I could justify the purchase of the new kind. If the difference in performance is as massive as some are describing here, that would likely be a priority, but I'd hold off as long as possible to even out my expenditure.
True, but as a percent of the cost the difference is minuscule. Also how many use a credit card to purchase and make payments? Thus that minuscule difference might be $.01 a month.
You're not wrong, although to some of us, every penny counts
As a general point here, I get that some people want the best of everything, but that's rarely if ever the case. Admittedly I'm much more laid back because I almost never shoot with two cards in at once, and have no strong feelings about different formats (I'm not a high fps type), though I did invest in a higher-speed and -resolution CF card after getting the 5Ds. I'm sure Canon's reasoning in offering mixed card slots is based on experience and feedback, anyhow.