E.g.: "The classic example of rent-seeking, according to Robert Shiller, is that of a property owner who installs a chain across a river that flows through his land and then hires a collector to charge passing boats a fee to lower the chain. There is nothing productive about the chain or the collector. The owner has made no improvements to the river and is not adding value in any way, directly or indirectly, except for himself. All he is doing is finding a way to make money from something that used to be free."
https://en.wikipedia.org/wiki/Rent-seeking
E.g.: "The classic example of rent-seeking, according to Robert Shiller, is that of a property owner who installs a chain across a river that flows through his land and then hires a collector to charge passing boats a fee to lower the chain. There is nothing productive about the chain or the collector. The owner has made no improvements to the river and is not adding value in any way, directly or indirectly, except for himself. All he is doing is finding a way to make money from something that used to be free."