Okay, well, I'd only be miffed if it were my Luna bars b/c those are expensive!
Really, how is it worse for them than a regular treat? It's most likely healthier, with just as much sugar, maybe even less sugar. Obviously, if your treats are like grapes, carrots or apples or homemade granola they will be more sugary, but the regular kid snack, like fruit snacks, cookies, jello cups, cheese cracker handisnacks or whatever... no I wouldn't worry about it, way healthier than those.
EDITED TO ADD:
The protein, especially with the bar cut in half isn't going harm them in any way. They got between 2g and 5g anyways depending on the flavor of the bar.. that's less than a cup of peanut butter, or less than one egg, which is about 6g of protein. Tell your health food nut husband to read labels.
Nutrition facts here: http://www.myfitnesspal.com/nutrition-facts-calories/kell...