This is because even replacements are produced according to generally accepted standards.In contrast, cheap printer toners can be released for sale by companies that can reduce the cost of their production or be covered by some kind of promotions or rebates. Thanks to that, their buying does not strain the home or company budget and allows for even bigger savings.
Their prices are becoming more affordable and operating costs lower.Multifunction devices offer increasingly larger scanning resolutions, less margin, larger formats, etc. But still, such home printers are far behind the professional equipment used in professional printers.
Not to mention the much larger range of techniques used, which have nothing to do with those we know from home printers.
Printed roll, solvent, water, anhydrous - long to exchange.
The quality of such printouts is higher, which entails the obvious higher costs of printing itself.
Professionals usually use one or two proven programs, which translates into their high productivity. In the work of graphics or DTP operator you usually need a program for processing vector and raster graphics.