BackforGood, that's a good point. My boys are just turned 2 and nearly 5 so it's young children I'm particularly thinking of. DS1 has lots of food allergies and both boys have a number of intolerances so their diet is more restricted than the average.
I wonder though whether the range of things they eat is not that different from the average because we feed them a range of less common foods e.g. no wheat, but 5 different types of legumes in breads & muffins. Plus my experience is lots of kids are fussy and only eat a smallish number of foods.