I'm guessing because: 1) A lot of middle class folk who buy houses see it as an investment, and they hope to seem some return on that investment driven by risi

I'm guessing because: 1) A lot of middle class folk who buy houses see it as an investment, and they hope to seem some return on that investment driven by rising prices. 2) A lot of middle-class folk tap into their home equity to pay for major expenses (see HELOCs and 2nd Mortgages). Rising home values give homeowners more equity to tap into.