Are you talking double knit cotton - which can be very stretchy
or
The heavy double knit polyesters? Some of them had/have little or no stretch
Different knits have different characteristics. Some are so stretchy that they can almost double in size in both directions - some are so stable that denim seems stretchy by comparison.
I would use the not very stretchy pieces for utility quilts - the ones that you have in the trunk of your car.
Remember the old pictures of beating out a fire with a quilt? Those were heavy ones made of wool.
I would not try that with a blanket/quilt made of synthetic fibers or a synthetic fiber batting.