This may include say a dog that considers me part of it's group but not a wold looking to eat me. Large groups are so recent in evolutionary terms as to be irrelevant. Nations and companies etc may be exploiting traits benifitial in much smaller group sizes.
Remember cost benifit is non linear, which is why trade for example happens. I might spend more resources than I receive while benefiting more than it costs me.
PS: The article is talking about different degrees of publicity, not nessisarily true anonymity.