saying that "purchasing is a voluntary decision" is kind of ridiculous. sometimes it's not. printer cartridges are a good example, because most of the major manufacturers do similar things with their cartridges and say you shouldn't reuse them. taking this further, they also say that you shouldn't put generic cartridges in your printer. a printer is something that in many situations (eg businesses) are not optional

if you switch shouldn't to can't (like lexmark is asserting) then it's not a choice

*edit for clarity