Handpainted needlepoint canvases are a luxury for many. Yes - they are more expensive than the silk-screened canvases and other mass-produced techniques -- yet the time required to paint a canvas by hand is extremely long.
The finest canvases use natural pigments finely ground - then mixed with natural adhesives.
Depending on the design - often these canvases are stitch painted - carefully painting each stitch onto the canvases - as seen below.