Coffee consuming classes

In a new book, Consumed: How Shopping Fed the Class System, by Harry Wallop, the author discusses how what we consume is linked to our identity as consumers. In an item on BBC Radio 4's Today Programme, Harry Wallop mentions three consumer segments:

1. Asda mum's - who want the security of a well-known, good honest brand
2. Middleton Classes - who enjoy trading up and purchase products such as Tesco's Finest, and Sainsubury's Taste the Difference
3. Wood-burining stove gang - who care deeply about what they consume, and would be appalled about buying anything branded

The book includes several other customer segments.Whilst these segments are necessarily generalisations, they do help us to visualise the customer segments and bring them to life. 

However, one should question whether these segments are accurate across all products that are consumed. If we look at involvement theory, it is possible that a consumer is deeply concerned about one category of products and much less discerning about another; and therefore a Middleton Class woman might be fiercely loyal to her corn-fed, free range chicken and yet be quite happy to buy Tesco's Value kitchen foil.