When do you want to know if a printer is running out of ink? I think the answer is: when you want to print to it, or if one of your jobs is printing or queued to be printing on that printer. If you're not printing, then unless you're the person maintaining the printers, you don't care.
Also, when you're ordering cartridges for several printers (not necessarily the same model or on the same machine) and need to know if you should order some for this one.
