So it's not that "sharing is the norm" it's a difference in the understanding of ownership and property rights. Otherwise why not share the food and share the housing, since sharing is the norm and not the exception when it comes to property rights?

Otherwise why is sharing the norm in one small specific instance and not the rest?

The original statement was in the context of IP. In this case, no one has anything taken away when it is shared. Sharing physical goods requires them to be taken from somewhere/someone... not so much for digital information, which can be duplicated infinitely.

This is a funny comment in the context of a discussion about a (nominally) communist country.