Guy's there is nothing magical about chocolate milk. It is a casein based protein (slow digesting), with sugars. In my opinion, it's inferior to a properly balanced homemade shake made with whey, which is much faster digesting (which means amino acids break down into muscle cells quicker post workout + insulin spike from sugar/whey mix). There is no arguing the benefit of a fast digesting protein shake post workout.
If you find you respond better to chocolate milk, I would suggest you aren't getting enough protein from animal sources (slow digesting, complete amino acid profile).
Lot's of bro science in here