What is the main idea of this passage? [br] [originaltext]A libertarian think t

A libertarian think tank, reckon that eliminating all travel visas to the United States would add between $90 billion and $123 billion in annual tourist spending. By one estimate, introducing visa restrictions can lower trade and foreign direct investment between a pair of countries by as much as 25% .

But the demand for locally grown foods is colliding with another powerful force; a booming real estate market, particularly in the Hudson Valley, driven by waves of newcomers from New York City, perhaps drawn by the region’s natural beauty, more relaxed pace and less expensive housing. The boom is gobbling up many family farms as owners choose to cash in on the surging value of their land rather than grapple with the perennial challenges of slim profit margins, high taxes, long hours and fickle weather.