If it's quilted and bound I keep my mouth shut. If they have an opportunity to fix it, I tell them. Then it's up to them whether they want to fix it or live with it.
A lady came up to me at a retreat and asked if I wanted to know the mistake in my tote bag. I didn't make the bag, it was a gift, and had been using it a couple of years at that time. She told me anyway. I'm still using the bag and no one else has ever mentioned it.
Susie