LBH, believe or not, I eat vegan. Vegan food does not have the protein density of animal products and I found long ago that I had to do protein shakes to add any muscle. Even then, when I started learning diet information from this board and tracking my macronutrients I was shocked at how little protein and calories I was getting relative to a true bulking diet.
In order to get enough calories on a vegan diet it is very easy to get too much fat and not enough protein. It probably can be done, but you are likely talking a lot of beans for protein, and typically soy products. With soy the issue of estrogenic effects comes up. The protein shakes just make it easier. I use a non-soy vegetable protein mixed with soy milk and sometimes soy yogurt -- enough soy protein to get the positive benefits, but not too much. BTW, I don't have any proof to this effect, but I have some suspicion that the soy helps with PSA levels (0.5 at last blood test). I also sometimes add cranberry juice to the mix for workout glycogen.
Anyway, calories are calories and protein is protein, so I have no trouble bulking as long as I am eating properly to hit my macronutrient targets. I know some will argue with the protein point, but as long as the amino mix is reasonable it seems to work.
I have not been doing any Omega-3 stuff up until now, but I am on a cutting phase now and need to up my fat intake -- I expect I will add some flax oil to the protein shakes and, perhaps, try that veggie DHA supplement.