1) Money exists to serve humans. It doesn't exist for money's sake. The end goal is to help people. The airline helped people get from A to B. Dropbox helps people send files.
2) The people holding the bonds are still gamblers. Your example consists entirely of gamblers!
Do you think the VCs who invested in Dropbox would do so if they knew that Dropbox would never allow itself to go public or be acquired?
By your definition, if I purchased Apple stock I would be "gambling" - Apple wouldn't see any of my money. In a certain respect I sort of agree with this, but it's also clear that when Apple went public the money raised was built on the expectation of future free trading in the stock so, as far as I can see, it is very difficult to divorce "investment" from "gambling".
So what do you think should be done about the present situation, if anything? I have no idea.
http://www.scribd.com/doc/26993356/Worlds-Biggest-Companies-...
[NB As I write this I am maybe 100m from their old headquarters!].