It looked like extortion because it was extortion.

From the excellent Perilous Fight by Stephen Budiansky, an account of the naval aspects of the War of 1812. Page 84.

Meanwhile, foreign depredations on American shipping intensified. Despite endless diplomatic negotiations in London and Washington, Britain had only escalated its clampdown on American trade. Since 1807 a series of orders in council—proclamations issued by the British government through royal prerogative—had in effect abrogated Britain’s adherence to the international law of neutrality by barring all neutral trade with the Continent. The only exceptions were for merchant ships that first put into a British port and obtained a British license to proceed. Napoleon retaliated with edicts banning neutral vessels from calling at French-controlled ports if they had touched first at a British port. American shippers were now damned if they did and damned if they didn’t. Each of the warring European powers admitted that its act was contrary to the law of nations, but justified it as a retaliatory response to the other’s illegal acts. By the end of 1811 the total number of American ships seized since 1803 was approaching the 1,500 mark, divided roughly two to one between Britain and France.

What made it all the more obnoxious was that, in practice, the orders in council only seemed to reinforce the obvious conclusion that Britain’s real aim was not so much to deny France trade but to make sure Britain benefited from whatever trade occurred. The British government sold as many as twenty thousand licenses a year to shippers who wanted to trade with the French Empire; bought and sold on the open market, they fetched up to £15,000 apiece. The blockade, justified as a military necessity, was looking an awful lot like a system simply of legalized extortion.