They’re not “space Jews”. Most of the actors that portray Ferengi are Jewish. Also Armin Shimerman, the most famous Ferengi actor, says it’s mostly Americans that think the Ferengi are Jewish.
“In America, people ask ‘Do the Ferengi represent Jews?’ In England, they ask ‘Do the Ferengi represent the Irish?’ In Australia, they ask if the Ferengi represent the Chinese,” Shimerman said. “The Ferengi represent the outcast… it’s the person who lives among us that we don’t fully understand.”