Jesus Christ . . . It must suck to be a slave to food.  Since high school, almost 40 now, I eat what I want, when ever I want, and don't gain weight.  I have weighed 215 - 220 for the past 20 years.  if i only drink water and no alcohol, I drop to about 200.  Now I am back at the gym because I want to, beat up people. 
Oh I don't have rules about food.  I too eat however much I want and never gain weight - still 155.  
I think I have different ideas about what food is than most people.  For me, food generally doesn't come from a box, a bag, a carton or a drive-thru.  The edible things that you'll find in those places are things I don't want to consume since they don't register as food.  I've seen the effects on people who eat that stuff, and I choose not to do that to myself.
Just because something is edible does not make it food.  It must suck to be a slave to not food.
FWIW, the idea of a 3:30 banana came about because I bring a banana with me as an afternoon snack.  After months (years?) of doing this, I noticed that I almost always got hungry at around 3:30.  Once I connected those two ideas, the name stuck.