Just do like the one lady and when they donate "x number of dollars to your fabric fund" you will give them one....:)
Nonprofits do it all the time...give us $25 and we'll send you a book, etc.
Or as some suggested, have them buy the fabric separately and then pay you to make the item. You could make up a bill like that.
But I think you worry too much. :) How many are you making anyway? Who is going to complain and where would be the proof that anyone sold anything to anyone once you were done if it is just for a few friends and their friends?
I'd think they have "bigger fish to fry". Maybe I'm wrong, but hard to believe any company would go after someone who make 2 or 3 of something (even if they didn't want them to which is debatable according to many of your references). It seems way more trouble than it would be worth to the company.