I wash mine for several reason's.... first, I don't want to worry about shrinkage so I do wash them in warm water and then there is color bleeding..had some from Gee's bend that I ended up tossing as it wouldn't stop bleeding..
Also, I have alot of allergy problems and I don't like to smell the dyes in fabric so I do wash and dry all my fabric. When they come out of the dryer I fold right away. When I am ready to cut or use them they are not badly wrinkled, smell better, feel better and I can starch and iron any then.