I feel like my post isn't very clear.
My point is that Vegans are on a diet. "non-vegans" group together every other kind of diet in the world and everyone who isn't on a particular diet (has no rules). 
When you do it that way, you can say that about any diet: "paleos live longer than non-paleos," "low carbers live longer than non-low carbers," etc.
You need to compare diet to diet, and I guess I'd like to know if the lack of animal products is actually why vegas live longer, or is it just the eating better in general. Could I incorporate an extremely healthy and well balanced diet that includes animal proteins and live longer than vegans, on average? 
It's a legit question.