if it's good fabric a little bit of a press will straighten out the ends. however, it's also true that you lose about 1/4" on each end because of the ravels and frays.
i tear my own fabric when i want just a hunk off a long stretch, so i don't mind it when i'm shopping. BUT i do politely ask that they measure carefully to make sure that i get a usable amount that's equal to what i'm paying for. so far, i haven't gotten ripped off. (a very bad pun, i know, but i couldn't resist. :lol: )