Printers are real world devices. They can't operate virtually, like so much of the rest of the world. The actually have to make a difference in the physical world.

You are correct, they exist to sell ink (or toner). The printer box is much more expensive to make that what it is sold for. This is not surprising considering the myriad of functions they must perform to get a copy of one's tax form onto paper. Printer companies do their best to stay in business by preventing others who do not bear the cost of the box from getting the profits from ink. They may gouge consumers, but there are reasons.

Calling them "terrible" does the entire class a disservice. A cheap shot. Think back to daisy-wheel and dot-matrix printers. And also think of the tasks they must perform.

Doing an extremely difficult job imperfectly is far better than never doing the job at all.