Not all cotton batting is the same. Some is needle punched through a scrim and more stable (the Warm and Natural brand is like this), others needle punched with no scrim (like Quilters Dream brand), some have binders (adhesives) to help it stay stable until it is in the quilt, some don't. Not all cotton battings will hold up to a prewash or popping in the dryer damp as they were never intended to do so.
You need to adhere to the minimum quilting requirements stated on the packaging and remember these are the absolute minimum your quilt spacing needs to be in order for the product to maintain integrity. I usually exceed these requirements and quilt much more. More quilting will help stabilize and reduce the amount of shrinkage. Many times the minimum quilting requirement will give you an indication of what manufacturing process was used. If your minimum distance is 8 to 10" that is usually a good indication that scrim and/or some kind of bonding process was used (but not always, as is the case with Quilters Dream brand which doesn't use a scrim or bonding agent). A minimum distance of 4" may indicate the batting will not hold up well to pre-shrinking. A minimum distance of 2" would definitely mean don't try to preshrink the batting and also may mean the batting will shrink up and give you a very crinkled antique type look.
As far as the "crinkled look" sometimes this is a good thing as it can hide imperfections in your quilting.