What afflicted the people of Nottingham was GOVERNMENT TAXATION and government hunting restrictions. Robin Hood (in the capable hands of Ridley Scott) is protesting oppressive taxation and arrogant government.
"what plagues England in the Robin Hood story is never poverty per se, but taxation. Invasive government taxation and hunting regulations have reduced the English peasants to penury. The King, the Sheriff and other government toadies are the people’s enemies. And Robin Hood, far from trying to redistribute wealth, is merely attempting to get the people’s money back from these bloated tax-and-spenders."
Once again, government is the CAUSE of poverty. And limiting the power of government is the solution to the problems that government creates.