When they rip the fabric, it does stretch a bit, but in the olden days (60's-90's), they "gave you" a couple extra inches!
Now the few stores I shop in, are down to the exact inch! Hellloooooooo???? what about shrinkage? not to mention the uneven cuts. Sometimes, esp. with young salesgirls, I watch carefully that I'm getting the yardage I asked for.