The flow of a currency is crucial to its existence. If no one would spend bitcoin, it would not take long until its eventual death.
most of the transactions right now are related to buying and selling btc. if btc was on the brink of death people would start selling there btc and this would increase transactions.
but also this might create a run and price collapse.
That is right. And most of the tranactions are very small amount. I think the gambling is a large proportion of the transactions.