Refilling the ink in a CISS is pretty simple as well, just take your time.
This is for a laser printer. No worrying about drying ink heads.
But now you've got me curious -- who is printing 10's of thousands of pages using an inkjet? I would have thought that anything at volume is laser, with the exception of photo printing.
I've hesitated on actually trying this though as there's usually some details about keeping an old firmware version or something to make it work.
Specialty applications such as large-format inkjets (eg 3ft/1m wide continuous roll paper), edible ink for baked goods applications, custom inks for branding/proofs/industrial, and so forth. My favorite was a specialty cake printer that was designed to print directly on the icing of a cake, not on an edible wax or fondant sheet (which always seem like cheating to me).
There are quite a few applications where desktop-like inkjets are used in high-throughput modes. They either don't sit idle long enough to suffer from dryout or they're built to deal with it. They do automatic light clean cycles and some models have rubber gasket head parking areas to seal the heads and prevent ink evaporation when idle. Some manufacturers also sell auto-cleaning units so the printer can do a full deep-clean automatically.
I'm not counting true industrial applications (eg packaging expiration date print heads) since those aren't usually document-centric nor do they speak desktop printing protocols like PCL.
Laser only exists for offices, : black and white printing, unsteady usage patterns, fast printing on small scale, replacing cartridges are administratively challenging.