I'll try to cover that in http://understandingblockchainfreedom.com at some point. You could answer by asking them a question:

How did a pizza sell for 10,000 bitcoin in May of 2010 and now that is worth millions of dollars? How does that happen?

For people to understand the increasing value of cryptocurrency is quite a wild ride. It involves a full deconstruction of what money and value actually is. For many, it's not a comfortable conversation because they spend their lives trying to obtain something they don't even understand. Certificates of debt verses market supported tokens of value... it's quite a paradigm shift.