Any other VERY HUNGRY veg*ns out there have trouble feeling full?

I just got this box from Borders, and while it is quite large (almost 4 cups!) and I am one who definitely needs to use bento to control my diet, I actually am pleased with the size. I am a vegan-leaning vegetarian, for 2+ years now so it's not like I drastically changed my diet recently, and lately I simply can not reach a point of satiety. I pack a healthy amount (1 cup of brown rice, about 1/2 cup of beans or occasionally tofu, and some veggies and fruit) into a 2.5ish box I have, but this just isn't cutting it.
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Does anyone else eat their bento too soon?

I pack myself a bento on the days when I'm taking the kids into town and staying at university (where I am no longer a student, but I just can't be bothered driving home when I know I'll need to drive back in a few hours). I just hang out in the student lounge at the Catholic chaplaincy, and find if I have a bento lunch I usually have to eat it before eleven because I just can, and it's so delicous, sitting there tempting me with it's smiley Kitty face. Then I'm hungry by 3, because I ate too soon.
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