I get interviewed a lot more than interviews with me get published. I think it usually starts with "Dr Delaney, would be really interested in talking to you about how people make decisions etc.,". I then get asked a few preliminary questions. At some stage in the interview I get whipped into a frenzy and start talking about pretty much every thing that I think is interesting in behavioural economics and its relation to policy. I then snap out of the trance, get down off the table etc., and what follows is usually something like "The philosophical basis of rationality and the state is interesting Liam but I guess what we would really like to know is what does this literature say about how people actually behave in the supermarket".
For people interested in the supermarket question, I am not a great guide. I spend about 2 hours annually in supermarkets and I don't enjoy those two hours. That's one of the reasons why I really liked Paco Underhill's book "Why we buy", giving an insight in to how hard-core shopping observation people think and research. This is a well-written book with a sympathetic narrator who has, along with his company, spent decades effectively stalking people in retail outfits, examining exactly what people do at all stages of the retail process.
There is no theory in this book and the author is clear that he made a decision early in his life to go for extreme observation rather than academic theory. Many of the more interesting things in the book come from the detailed studies the company conducts examining people's behaviour in retail stores. His company have been looking since the 70s at detailed things such as eye-level of the product matching the target group's height etc., One thing the author really emphasises is to make sure customers are not crowded by other customers when they are browsing and particularly not by other customers they would not relate to. The book gives some insights into time-of-day patterns in shopping, the effects of interaction with the staff, the effect of layout etc.,
There are certainly behavioural interpretations of many of the effects described in the book that would be worth talking about, particularly in trying to explain why immediate convenience has such an effect on people's spending behaviour. This book is useful and feels a bit like a conversation with someone who really knows retail behaviour.