They can and have - a nice example of this is Norway vs the UK\Scotland. When oil reserves were found in the North Sea both Norway and the UK had claims which were (iirc) roughly similarly sized. They chose completely different paths, with Norway establishing a state owned oil company (Statoil) to handle exploration, extraction and processing with stipulations on what should be done with the windfall. The UK ended up selling licenses to private companies to handle this themselves.

As a result of this Norway now has the largest sovereign wealth fund in the world. It's pretty hard to make direct comparisons given the differences in their populations and economies, but a fairly broad range (i.e. left and right [1][2][3][4]) of people seem to think that this was a wasted opportunity and that if it was managed better they'd have a lot more to show for the last 3 1/2 decades. I'd tend to agree.

[1] http://www.theguardian.com/commentisfree/2014/jan/13/north-s... [2] http://www.bbc.com/news/business-19871411 [3] http://www.economist.com/news/special-report/21570842-oil-ma... [4] http://www.newstatesman.com/politics/2013/04/thatcher-and-no...

edit: A little more digging seems to indicate that I was painting with slightly broad strokes. Norway do indeed operate some sort of licensing scheme according to the "North Sea oil" wiki page (http://en.wikipedia.org/wiki/North_Sea_oil), so it is not entirely operated by Statoil.

Norway certainly does have private exploration too, but note that we also levy massive extra taxes on oil companies, which adds up to something like 70% total, vs. 28% corporation tax on the profits of most other businesses.

I believe the licensing system also takes into account investment and effects on local economy to an extent that creates substantial capital inflow beyond what you'd otherwise see.