This question is phrased as if Pigment dye is excluded from Garment dyes, when in reality pigment dye is typically a pigment “wash”, which is a form of garment dyeing. There is no such thing as garment dyed fabrics, only garment dyed garments.

Garment dye refers to dyeing a whole garment after it’s sewn together. This is often done with special wash chemicals, like burn-out, or like Pigment. So pigment can be used in a garment wash, and in fact it is much better as a garment wash, because piece-dying (dyeing the entire fabric roll, before cutting) with pigment will create shading on the roll. If you cut panels from the un-evenly shaded roll you will build garments that have seams with color shades that don’t match — not usually a desired look.

One major issue — Pigment dyed fabrics have a propensity to crock, ie transfer color. Color transfer is much more common with pigments since the pigment will effectively “sit on top” of the fabric instead of truly changing the color of the fabric by embedding into the yarns as normal dyes do. If rubbed against lighter colors, the pigment dyed fabrics can easily transfer pigment onto other fabrics or materials. If you’ve ever worn blue jeans that left a blue residue on another fabric, that’s pigment crocking. Blue jeans use indigo yarns, which are colored with indigo pigments, but there are almost limitless colors of pigments, though they all have similar qualities: produce uneven (some say “interesting”) shading, easy to crock (dye houses need to pay close attention), and lastly, difficult to work with.

Dye houses typically do not love pigments for may reasons, among them because they can leave the dyeing vats a mess, much harder to properly clean out between different colors, so the wash cost can be much higher if dyeing with pigments.

But the look of pigment-washed garments can be so unique that it’s worth dealing with all the above challenges. A dye house that knows how to work with this technique can help a designer execute impressive, classic looking items, that are actually new. A lot of perceived value comes from the fabric — wash and pigment dyes are an important part of creating that value.