I haven't been quilting long enough to run into this with quilting books, but I think it's the same as other craft books with patterns.
I will happily lend a book to a trustworthy friend, as long as they agree not to copy it. This is the same as a public library- one person is using the book at a time.
I will not photo copy patterns for other people. As well as violating copyright laws, it's unethical. You are stealing someone's work: they created it and published it and are selling it. By making copies and sharing them, you are taking away sales.
I understand what it's like to see beautiful books with patterns I love that I simply can't afford, but stealing is stealing. Instead, I'll see if my public library system has the book (they have a decent collection of quilting books in the system, but not individual libraries) and if they don't have it I'll look for a used copy of the book. With the internet, for most in print books it's doable but might take a few weeks.