This will not work if the thing lies based on the age of the cartridge as it will mean the price per page is much more expensive for people use the printer less

This will not work if the thing lies based on the age of the cartridge as it will mean the price per page is much more expensive for people use the printer less. In fact your attitude will probably systematically get you ripped off if you are an ordinary consumer. Since the price-per-page calculation in the review probably comes from an assumption that at the cartridge gets fully used, and the test was probably under a highish workload.