If by consuming a post workout shake a person somehow gains an advantage compared to not having one will for all intents and purpose depend on whether they've hit their daily macro goal. You can consume all the protein shakes you want but if your not consuming properly the rest of the day, it won't make any difference. It's really for the athlete where nutrient timing and food partitioning makes sense......for the rest of us a protein shake is just a good marketing campain to seperate us from our hard earned money. jmo.
Whether you think you can..... or you think you can't..... your 100 % correct.