[rtkwe]

I have doubts a commercial printer back then would handle the 3G acceleration and vibrations during launch and reentry well. There's also the issue of materials from the safety of them for fire risks to potential off gassing you wouldn't notice in an office but could cause issues in the enclosed recycled atmosphere of the shuttle.

A lot of the cost for space bound items are from R&D being concentrated in a few items but others are because it costs a lot to make sure they're not going fail or kill someone. Using this behemoth saves some of the time by reusing a military line printer that was likely already tested for shock resistance if it was used on ships and for fire safety for similar reasons.

There's also the potential military uses of the Shuttle which informed a lot of it's design. Military printer already has the decoding infrastructure if it needs to be built in with known key management etc you'd have to build seprately for a commercial printer.