Well, many investment opportunities out there, like Forex and HYIP accepts Bitcoins.
it is sad to see a Hero Member call HYIPs as an investment opportunity for bitcoin!
What do you think those companies do with the bitcoin they get? Do you think they store them? Sure a part of those should be stored, since now you can pay almost all services online with bitcoin, host, domain ,security, but remove fiat exchange and you will see the bitcoin market services disappear instant. Bitcoin has value in fiat, and several companies, merchants just work with bitcoin because then can exchange it to fiat, taking their profit, dont be blind bitcoin needs more fiat then the reverse.
it doesn't matter what those merchants do with their bitcoin as long as they accept bitcoin, it gives bitcoin real value and it helps with the adoption which is important more than anything else.