Solid ink printers, also known as phase-change printers, are a type of thermal transfer printer.
They use solid sticks of CMYK-coloured ink, similar in consistency to candle wax, which are melted and fed into a piezo crystal operated print-head.The printhead sprays the ink on a rotating, oil coated drum. The paper then passes over the print drum, at which time the image is immediately transferred, or transfixed, to the page. Solid ink printers are most commonly used as colour office printers, and are excellent at printing on transparencies and other non-porous media. Solid ink printers can produce excellent results. Acquisition and operating costs are similar to laser printers.
Previously, solid ink printers were manufactured by Tektronix, but Tek sold the printing business to Xerox in 2001.Źródło: https://en.wikipedia.org/wiki/Printer_(computing)
That is why printing plants limit the amount of services provided.
Along with new and efficient printing machines, labels can be ordered even at very low costs without worrying about the exorbitant rate.
Of course, large outlays are still cheaper, but this difference is not as big as a few years ago. The potential market for low-cost prints is small, local companies producing small quantities of goods.
Recently also a lot of home brewers begin to label their own beers, of course not for trade, but for example for contests.