If you want to not include religious views why post it in this section, like things that make you think forum? Obviously, you do not want to acknowledge some peoples sense of right and wrong is religion based, in addition to other things. Your parameters for the answer are unfair, and you have a loaded question to begin with. A baby doesn't know not to pickup the cupcake, any more than a dog who found your steak unattended while went to the frig for a beer. Your senerio leaves facts to be assumed. The ages of the subjects, were they perfect strangers, brothers or sisters, made at each other, revenge, starving, senile, or just couldn;t care less if they ate off someones plate. Obviously one has to access cupcake ownership first, to justify taking the cupcake at all. If you know it isn;t yours, that tells you if its right or wrong.
I understand your meaning in a way, its kind of the same thing as social graces or boundries. Things that are just common sense or unwritten rules. Although taking a cupcake you know isn't yours, is a written rule, in our legal system and religions. And the question is the bulk of our laws are derived from religious things, like the 10 Commandments.
Can you show whatever code you go by, doesn't actually have its roots from Judeo/Christian beliefs?
Nobody likes a cupcake caper.