I don't think it's just that, although many have found it suspect that the dairy industry gave a lot of funding that helped the development of the original food pyramid with dairy as a core food group.

To me it's more like the current environment, to borrow a programming term, makes it difficult to "fall into the pit of success."

The NYT ran a great article on this a few years ago: http://www.nytimes.com/2013/02/24/magazine/the-extraordinary...