You could use area per capita as an indication of wastefulness.

Nothing is 'mere'. — Richard P. Feynman

Total consumption makes a lot of sense to evaluate the global impact of an individual government's policy. For instace, a 10% change in US consumption is more than enough to provide all of Italy's oil. If you look at oil consumption per capita, you'll find the Virgin Islands, Gibraltar and Singapore are the worst offenders. That tells you keeping a microstate going is expensive, but eliminating them would not solve any of the world's global energy problems.

So, first use the aggregate figures to find which political agents are associated with the biggest impacts, and then use the normalised figures to see which of those are inefficient.

Nothing is 'mere'. — Richard P. Feynman