You may have read this article by, Clive Boddy (Honorary Visiting Professor in Marketing at Middlesex University and Visiting Professor of Marketing research at the University of Lincoln) before so apologies for the repost.
It's an interesting read. Interesting because it misses a key point. That a PHD anthropologist is no better at conducting ethnographic research than a top rated agency planner with a first class honours in history from Durham, usability specialist or even a bright documentary film maker. I should know, I work or have worked with all of these people at one time or another.
The simple truth is that there is no qualification out there which can provide you with the thinking tools needed to observe & interpret spontaneous events, detailed behaviour, cultural backdrop and to translate them into meanings and business actions.
Before you accuse me of sounding too smug. I have made my share of mistakes in the past. But the biggest mistake was thinking that anthropologists alone were the answer.