howz about we all press our Logic Buttons here.

To suggest that a person shouldn't let others see her work unless she's willing to have it copied without her consent is illogical at best. i know there are car thieves in the world. should i leave my car in the garage? if i don't, is it then my fault if somebody steals it? should i feel flattered that he liked it well enough to steal it?

Copyrights are a matter of law.
They weren't written to facilitate our personal convenience.
The issue should not be examined or discussed emotionally.

it isn't about what we like or don't like.
it's about what is or is not technically legal or illegal.

sometimes things can be legal and ethically right.
sometimes they can be ethically right but not legal.
sometimes they can be legal but ethically wrong.

If Person A creates an original work Person B cannot legally copy it without Person A's permission.
period.

When it comes to the art and craft of quilting in particular the issues and questions regarding originality might relate to the finished item, to the design, to the pattern/instructions, and who-knows-which of many other details.

there are so many possible combinations of circumstances it would be nearly - if not actually - impossible to list and address all of them.

if you see a quilt you like and want to re-create simply ask yourself whether or not the design is your own.
if it isn't, the easiest and most courteous thing to do is to ask first if at all possible.

if that isn't possible then take some time; do a little research; determine whether or not the design is based on elements from the Public Domain. if it is, you are most likely on safe ground. if it isn't ... do the right and smart thing. resolve to admire it, but don't copy it.