I am probably off in left field - but having worked in products liability - I wonder if it might be more of an attempt to avoid liability if say:
You make a bunch of something with the same fabric and sell them - - and for a strange reason there is discovered a flamability issue - or something in the fabric questionable to children inhaling - get what I am thinking(?) - - in that case they may be trying to limit their liability by saying it is not for commercial use.
Don't flog me - - it just came to mind. :-)
Marysewfun