Having a straight/true grainline really matters to some people.
For others, they do not seem to care much one way or another.
I have learned that "permanent pressed" cottons will not straighten. I can pull and pull and pull - and they insist on remaining they way they were processed.
If a fabric design is printed off-grain - I guess the choices are to cut with the design and have off-grain pieces, or to cut with the grain and have "off" design.