If you want to wash them to remove the chemicals and get out the excess dye then go ahead. If the fabrics shrink to the point there is not enough of a fabric then consider what that would have done after your quilt is made. I have to wash all my new fabrics and if I had one shrink to that extent I would rather know it before the quilt is sewn than after.
I buy 1/4 yard pieces from time to time and have no problems washing them. You can put them in a mesh bag or pillow case, I just throw them in the washer. I have put a jelly roll in the mesh bags because it makes it easier get them out without stretching. I do have a salad spinner for those charm packs. For drying the 1/4 pieces or larger go in the dryer, the smaller or thinner cuts I partially dry in a mesh bag and then line dry the rest of the way (or iron them dry if I want them sooner).