Historically, people were more willing to "cash out" by spending coins during boom periods: https://blockchain.info/charts/n-transactions-excluding-popu...
That is what I was getting at, in order for Bitcoin to have a reason to exist people must spend them on goods and services. Bitcoin most likely would not exist for long if it became purely a store of wealth. Not that that will happens but many people are treating that way.
> no tax implications
Wouldn't that be tax evasion?
You avoid paying Capital Gains tax.
Gold is not currency because it's too damn expensive to store and move.
Capital gains tax evasion - maybe, I'm not a lawyer and I'm not advocating it. But it's clearly a motivation for some people to spend bitcoins directly without going through an exchange.