I'm not an expert in this field and am open minded about it if you have some evidence to share. I did a quick Google search and it looks like this is at the very least a disputed topic. Some research shows that there are some (albeit minimal) health benefits to organic food. Saying it is a gimmick seems wrong.

And I don't think anyone on the chain is arguing to abolish chemical fertilizers. We're talking about the health benefits of the food sold at Whole Foods, which may or may not be organic and/or contain certain additives.