Breakfast foods encompass a wide variety of food genres all summating to one startling truth: the time of day vastly affects how we eat. At night, it's OK to eat steak (unless you're in the South (steak and eggs)) and drink beer (unless you're from the South or in college (kegs and eggs)). These things are generally not OK in general society, in general. The Roman emperor Nero was one of the first people to differentiate between breakfast and later foods. His first decree, in fact, claimed that "the eggs of IV chickens shall be saved for each eating time before the house of Jupiter (the Sun (added by author)) rises fully in the sky." Long story short, eat eggs in the morning, not later. Nero also killed Christians with lions, a practice that has been more or less fully eradicated from our global community. Certain meats, you may have noticed, are certainly applicable to only certain meal periods. The aforementioned steak is mostly dinner appropriate. Hamburgers are a lunch staple. Sausage is a favorite amongst breakfast eaters. It seems, then, that meats are classified according to their level of grinding. Inversely. The more finely ground, the earlier the meat is eaten. I suppose then that a meat drink would be a fine 3am drink. I now understand why Australians eat Vegemite, which is, of course, as you may know, a euphemism for "meat jelly." They use it mostly on toast, prior to breakfast, in anticipation of koala sausage. Let's move on to breakfast drinks. Here's another relationship, this time direct instead of inverse. The fresher the fruit in the juice, the earlier the juice is drank. Examples: orange juice in the morning, Sunny D (I totally still drink this) for lunch, and wine for dinner. Furthermore, what makes it acceptable to drink alcohol in the morning? Mimosas! A little bit of breakfast-approved orange juice makes a copious amount of champagne completely valid for pre-8am consumption. Ah, the magic of fresh fruit.
P.S. I drew a graph to help you understand my point.