Salad Bar Arbitrage

This article, linked from Marginal Revolution, got me thinking about the concept of salad bar arbitrage, which first occurred to me a couple years ago.  What items at the salad bar are cheaper than they are in the nearby produce aisle?  Your mileage will vary, of course, but I find that the spinach and assorted greens are consistently less expensive at the bar than they are in the pre-washed bags and tubs.

A search reveals that very few people have pursued this subject, or at least posted their findings online, which surprises me.  I'd expect an entire site devoted to it in some city like New York.  Take a concentrated population of people, many with idle time, creative talents, and a hunger for cheap healthy food, and it seems like the blog posts write themselves.

I'm off in a few minutes to do some field research, but in the absence of any better information, I'm going to solicit input from my three readers.  Please e-mail me at the address provided in the right-hand column, and let me know what you find at your local spot.