Some is, like Murex Purple dye (which is from now-endangered shellfish and is almost impossible to get outside of a couple of traditional greek/italian craftspeople) it is prohibitively expensive to make the exact colour using synthetic dyes in a way that is safe for human consumption so it's used in food a lot, and that has revived the fabric industry as well.
Red was from cochineal beetles at one point but I don't know if it still is.
Some is, like Murex Purple dye (which is from now-endangered shellfish and is almost impossible to get outside of a couple of traditional greek/italian craftspeople) it is prohibitively expensive to make the exact colour using synthetic dyes in a way that is safe for human consumption so it's used in food a lot, and that has revived the fabric industry as well.