What is it that young children love more than their Christmas gifts? They love the boxes that they came in. In fact, even as adults, people often enjoy the boxes that they receive things in to a curious amount. Why otherwise would web sites set up lavish photo spreads devoted to "unboxing" new adult toys (I mean things like iPads and laptops, not the other sort you dirty-minded people)? Things are better when they come in boxes.
I'm convinced that one of many reasons the bento are cooler than bag lunches is that the food is nicely and tidily boxed for you, often with nifty little compartments to separate component parts. Of course, there is also the sheer artistry that many places put into such things. Sometimes, it's just the general arrangement with an artful sprinkle of black sesame seeds and a pickled plum (umeboshi) on the rice and a bit of plastic "grass". On rarer occasions, it's an entire work meant to resemble something else.
Even here at home, I prepare something akin to a "bento" for my husband to take for his lunches. I miss the niftiness of these boxed meals.