'cuz they want your stuff, man

The belief that wealth consists not of ideas, attitudes, moral codes, and mental disciplines but of definable and static things that can be seized and redistributed is the materialist superstition.
Tom Bethell paraphrasing George Gilder

Many of us free-marketers have unconsciously understood this.  The left disparages the notion of physical property as crass materialism not because they disdain material goods, rather they want us to loosen our grip on them, so they can seize those goods for themselves.  They confuse material things with wealth, they confuse money with value and love with sex, and are eager to equate spending with revenue, just as they wouldn't understand the difference between blood and saline if they were colored the same.