Marcos Galperin isn’t letting his vast fortune limit his freedom. The 54-year-old co-founder of MercadoLibre Inc., the most valuable company in Latin America, is walking with two reporters around the bucolic neighborhood where he lives in Montevideo, Uruguay. He’s worth about $10 billion, according to the Bloomberg Billionaires Index, but there are no bodyguards in sight. No one stops him in the street or even appears to recognize him.