Don't worry about what people with more muscle do....as it is easier to MAINTAIN muscle mass once you get there vs trying to ADD on muscle.
If you feel you are not getting enough protein, try adding in a Whey Shake with every meal (I only use powders for gaining, not maintaining). Add coconut oil or someother healthy fat to get the calories up there.
Lastly, get rid of all the crap in your diet. Building muscle is as much about nutrient utilization than it is calories. Eat crap, you will feel like crap and look like crap. Eat healthy and your body will respond in kind. The healthier you are and eat, the less you will need to actually maintain and grow. Hence why you see people putting on mass with the zone when they stick to all Paleo foods.