again, while some airlines might require this, it's not mandatory everywhere. my dad was a commercial pilot, and he said the only reason why the pilots eat different meals on occasion is usually because there isn't anything else available, ie he'll eat whatever is left in the kitchen. sometimes there might only be two sandwiches left, and that they happen to be different is pure coincidence, he'll just pick the one that sound most appetizing. he might discuss his meal choices with his co-pilot to make sure the co-pilot get's something he likes if it's available. the pilots aren't allowed to eat at the same time because one pilot needs to be at the controls at all times. so he'll usually wait for his co-pilot to finish his meal and possibly go to the bathroom before starting his own meal. if it's something quick and small like a homemade peanut butter sandwich, then it's probably no issue to eat at the same time (cuz it's 3 bites and it's finished)