It is really still good to invest than to gamble of course. Whenever, doing gamble is not become helpful to anyone or to any player in the gambling sites. While in investing you are creating profit and assets once its being done in the field of business like this in trading concepts as well.
I don't think they are equally at risk, especially if you compare gambling to invest in a S&P 500 index fund or in bonds funds.
I have a clear opinion on this: always prefer to invest rather than gambling, although as it had been said that one bitcoin is an investment in itself.
What most people wondering about these matters don’t have clear in their minds is that the higher the potential returns, the riskier your “investment” (I put it between brackets to consider gambling a kind of investment).
If I was wondering to spent 1 bitcoin in casino games, that would mean that I would have at least 100 times that amount divided in different assets: cash, low-risk funds, high-risk funds and stocks. And I would prefer to use that money for games like poker where I depend somehow on my skill.