Shadetree, I can only testify to my experience. Here in Florida, combating fleas was a way of life for me regarding my dogs. I had been using one product or another for seventeen years while here with dogs. I never even knew that anyone claimed switching to a raw meat, bone, and organ diet would help with the problem. Since switching about a year and a half ago to that diet, the anti-flea products I had (which had been previously in regular use) stayed in the the cabinet. There just weren't any fleas to use them for. Only then did I start researching the issue, since I could think of no other connection than that between switching diet and the disappearance of the fleas. As it turned out, this is a common observation, and the rationale regarding sweet blood made perfect sense to me.
PS I've seen lots of video on YouTube of foxes stealing commercial dog and cat food off porches, not to mention food from garbage. It's likely that many of them have incorporated these sources into their regular diets.
