Well yes, it's a chocolate 'candy bar', but hear me out. The peanut butter that it contains (as most of you know) is filled with protein, vitamin B3, folate, magnesium, etc.
The chocolate just helps ease the consumption of the peanut butter. And there's more peanut butter than chocolate, so really there is no reason to ever feel guilty about eating a Reese's.
I hope my research makes your day...