I do not believe that a colour laser printed can't switch to whatever tracking dots mono laser printers use when out of yellow ink. I'd believe laziness over compliance issues.

Citation needed about tracking dots on B&W lasers. I don't see why they're necessary: the main reason is for anti-counterfeiting. B&W lasers can't be used for printing counterfeit money, for what I hope are obvious reasons.

I don't know if they have them - but the same argument still applies. If you're printing in mono then no tracking dots are necessary, therefore stop complaining about missing yellow ink.