A FEW THOUGHTS ABOUT PLEDGING
The reason one looks toward the flag while proclaiming one’s loyalty is that flags are handier than complete maps of the United States, particularly since we added Hawaii and Alaska.
Of course, one does not absolutely need a symbol to focus on while pledging, and if one is alone and feels like pledging allegiance, one can dispense with the flag. Actually, one can dispense with saying it out loud.
However, assuming that the pledging is being done aloud in a room full of, say, third graders, it is probably best to have them all face in the same direction. Otherwise, they tend to make faces at each other. They might simply face the front of the room, but it would eventually be thought of as pledging allegiance to the blackboard.
Besides, pledging "to" the flag keeps them from asking difficult questions like, "Teacher! Teacher! What the hell is a republic?"