Doesn't matter if you're a body builder or a person simply looking to get into better shape - it's still good nutritional advice to follow. As I said to Blackshole, it might not be 'needed' depending on your goals, but it's still a good thing to aim for. Regardless, you're taking the discussion off the original topic.
Do you have any sources showing that 3 meals a day is as good if not better than 5-6?
I don't, other than personal experience & seeing what people around me have experienced. I personally prefer to eat more often, but it hasn't made any real difference for me other than controlling hunger. 2000 calories a day is 2000 calories a day, whether taken in three meals or in six.
I'm not arguing for or against either method, I'm just saying depending on the lifestyle of the individual, both ways work just fine. Again, in my experience.