I'm 6' and 180lbs.
Is 3000 kcal too much for bulking when my only activity is going to the gym 3 times per week while sitting in class all day and barely any walking?
Yes but its a bit more complicated than that. Fats take a long time to digest but not nearly as long as protein. Your body sucks the water out of veggies quickly and so they fill you up but quickly lose satiety. Protein is the most superior on that list because it sits in your stomach for quite a while. Fats will coat your stomach and cause you to feel satiated for a while because of density but though it will last longer. Best solution is to eat all of them. Metabolism and digestion are some of the least understood mechanisms in the human brain arguably just behind the brain.
just to clear things up, if you put refined sugar in a stomach, it would look pretty similar to the refined oil in that picture.
also satiation has almost everything to do with protein intake, and very little to do with fat.
all you need is your .45g of fats per pound of LBM to keep your hormones in check.
but seriously, VLCARB diets haven't been accepted in academia since 2009ish and with good reason
i can dig up the relevant studies if you want to play the /sci/ game