I agree. There's two ways to handle this. First, buy a printer that uses separate ink cartridges for each color. That way you don't have to throw out a mostly full cartridge just because you used one color more than the others.
Secondly, I usually continue to let the printer run until it is really out of ink/toner (or low on ink/toner). I've had B&W laser printers that print hundreds more pages after the toner cartridge says that it's empty. My inkjet printer at home has been telling me that it's out of yellow for months, but every time that I print something with yellow on it the output is just fine. I won't bother replacing the cartridge until the yellow becomes streaky or stops printing.
The thing to keep in mind is that the inkjet printer business is like the razor business. They sell the printers for dirt cheap and then charge you through the nose for the ink cartridges (cheap razor + expensive blades). There are all sorts of tricks that the companies use (ALL of them use them) to sell more ink.
For example, all of the printers come with ink cartridges. But what they don't tell you is that the cartridges they come with only have 1/4 to 1/2 the capacity of the ones that you buy separately. So when you buy a printer, a month later the cartridges run out. So when you buy a replacement you buy more than one set because you figure you'll run out in another month (which you don't).
Another trick is the software that "calculates" when the cartridge should be empty and tells you to change it. Why would you need that whenever you could just as easily have a sensor that detects the level of the ink reservoir? Plausible deniability I think. They can say that the software only provides "an estimate", but if they had a sensor that actually measured the level then they'd be accused of fraud if it wasn't accurate.
In the inkject business, it's all about selling cartridges.
Back to the original question about the Canon, I have never had a printer die on me because I ran it out of ink. When a cartridge is truly empty, I replace it and everything is back to normal. And on the off chance that it actually could damage the printer to run it dry, who cares? Inkjets are dirt cheap these days, and every year they get faster, higher resolution, and cheaper. At this point, anything that you're likely to still be using after a year is considered disposable.