I also do not prewash unless I think there is a reason to. Some fabric is so stiff off the bolt that I might just to get out all the sizing or whatever it is in there. I actually won't buy fabric that doesn't feel nice, but I have a sewing friend who will buy anything, so her stuff will often be washed before I will use it (or not). We pool all of our fabric at my house, but her taste in fabric is so far from mine that it is rare that I want to use hers anyway.