I've recently purchased a book entitled The Culture of Knitting by Joanne Turney, published by Berg in 2009. The author is on the faculty of the Bath School of Art and Design (in England) and the notes on the back cover indicate that she specializes in the study of textiles and fashion as "material culture".
The title caught my eye as I've long felt that it would be a worthwhile project if a sociologist studied the importance of knitting and how it appeals to such a wide spectrum of devotees. I've found it very interesting on my tours that such a diverse group of travellers--who come from a variety of locales all over North America and have a wide range of ages, backgrounds and interests--are drawn together in such a cohesive, compatible group. As far as I can tell, the common factor is a love of knitting and all it encompasses.
I haven't had a chance to read the book in detail, but from what I learned from a quick scan, it deals with knitting from a variety of angles. Although, ironically, I didn't see the subject of knitting tours and travel described. Something for a future edition!