Why Did I Eat That Whole Cake?

Last night, I found myself in the kitchen at midnight craving something sweet. As I rummaged through the fridge and cupboards, my eyes locked onto a chocolate cake that was supposed to be shared with classmates tomorrow. I rationalized it as a way to understand my late-night snacking habits, I wanted to see how much self-control I really had. But by morning, there wasn't an inch of cake left. Am I just weak-willed, or is this common for everyone? What's the point of science if not to indulge in forbidden pleasures? Help me, fellow scientists and snackers, am I alone in this?