This just in from the Special Diets Department at WDW:

“Due to the higher cost of dietary products, some items have an increased price. As items vary by location, we encourage you to inquire at each venue prior to your purchase. If you purchase the meal plan, it is considered a regular meal and you will not be charged for the difference.

I guess that means that if you aren’t on the dining plan you may encounter some higher prices on foods, depending on the location. While I’m slightly disappointed, I’m not entirely surprised as grocery shopping normally (for me) is higher than non-dietary restrictions grocery shopping. Hopefully, the increase won’t be too hefty.