In the United States, we've had the National Helium Reserve since the 1960's. Unfortunately, the decision was made in 1996 to privatize the reserves, starting in the mid-2000's. That's much of the reason for the scarcity we face now.
(Hey, it's not any more or less plausible than what you said.)
What's sauce for the sad alien is sauce for the human empire, say I.
For most resources it seem that they dont run out and the prices dont skyrocket in the apocalyptical. I have seen books from pre-1900 that were warning of the eminent "peak coal".
Their is an issue if their are no useful property rights like you can see in whales and you race to the bottum.
Don't forget the other effect on sea life when they're released near water:
http://balloonsblow.org/impacts-on-wildlife-and-environment/
Aren't you the optimist.
In addition to that, they'd then need to have a helium storage facility that could accommodate such an enormous reserve, the construction and maintenance of which might eat all of the profit from resale which might ensue.
All of this presuming the government would sell a sole bidder their entire reserve in one fell swoop.
[1] - http://minerals.usgs.gov/minerals/pubs/commodity/helium/mcs-...
If storing the helium plus interest rates actually costs more than the expected price increase over time warrants----then the US government _should_ sell off the reserve now, and the whole thing about them selling too cheaply is nonsense.
Though it might be that the US government can store helium cheaper than anyone else. In that case, perhaps they should sell the helium with the storage facilities? After all, what good are the storage facilities to them, when they've sold all the helium?