The New York Daily News reported more than 40,000 ultra-Orthodox Jews came to the Mets' home, Citi Field, and 20,000 others to nearby Arthur Ashe Stadium for the Sunday rally.
The rally's organizer, a rabbinical group called Ichud Hakehillos L'tohar Hamachane -- the Union of Communities for the Purity of the Camp -- said Internet use can lead to pornography, child abuse and other immorality.
Women were not among those at the stadiums because of separation of the sexes, and 15,000 Hasidic women watched speeches at six sites in the New York metropolitan area through a live-stream on the Internet, the News said.
The group's spokesman, Eytan Kobre, who operates a Jewish family weekly magazine in Brooklyn, said the group is not urging a ban on Internet use but wants filters.
"With one click, all of a sudden, you lose control and are whisked away to a world you never intended to see, and it overtakes your life," he said. "As a community, we are asking, is it worth it?"
He pointed to social media sites such as Facebook and Twitter, saying they can lead people away from prayer, community and family.
"I know that Facebook ruins marriages," Kobre said.
Couple calls 9-1-1 over missing hash browns; assault McDonanld's employees
Exploding whale video goes viral on Internet