Washing ALL quilting fabric before cutting it is an absolutely essential step for me.
I really don't understand the people that will wash a large piece of fabric for all the usual reasons that people wash their fabric before cutting it - won't wash smaller pieces before using them. But - their monkey, their circus.
As far as starching - especially on fabrics that want to ravel badly - which I try to avoid - it does seem to cut down on the loose threads on the back of the piece.
And does make the final pressing look prettier on the back.
I just like to know how my fabric is going to behave after it's washed BEFORE I go to the effort of making something with it.