I would keep her clueless! If she knew how much money and worth a quilt has, she would blab it to your hubby.
My sister used to be one of those persons. Always the comments and snide remarks. Now she is hinting for one. LOL!
On the other hand, envite her to go to the quilt store with you. That would open her eyes to the reality of quiltmaking. That is if you can stand to be around someone like that.