[tomohawk]

If you really believe this, do you lock your car? Your house? Do you let people just walk into where you live and eat your food and use your stuff?

Isn't it just arbitrary that you're excluding others from enjoying these things? What right do you have to have exclusive use of anything?

[alexandercrohde]

Yes, it is arbitrary. The idea of "ownership" is just an construct/idea self-aware matter (i.e. humans) happened to come up with because it worked well at that phase in our evolution.