The difference between us back then and us now is context. We live in an age of complete overwhelming external stimulus. You see food or calorie-laden drinks everywhere you look. The point of routine, which is also an evolutionary trait, is to reduce reliance on willpower and avoid wasting energy on making decisions. These are real problems that we have right now because of our body's greedy, opportunistic behavior (which was evolutionarily advantageous when food wasn't so abundant and also had completely different forms).