we're talking - i think - about copyrighted/licensed fabric.
it's a bit different in regard to copyrighted patterns.
even then, not all of the restrictings creators and publishers try to impose would stand up in court.
i encourage everyone to do the research, be as considerate of designers as we'd want others to do for us, and make only reasonable use of fabric, patterns or both.
it's absolutely a good thing to want to do the right thing. just don't start from a place of worry and fear.
chilllaaaaaaax. pour a beverage. start reading. ;-)