“We’ve become used to a system here, and a way of life,” explained Ola Mahmeed, 26, a mother of five who was applying for a two-day “vacation” to visit relatives in nearby Irbid. “There’s order, in terms of security, in terms of services. Anything I can think of I can find now in the market.”

Zaatari’s occupants say they would still jump at any chance to leave. Complaints are rife about electricity, which since June has been available only at night; rationed water; and, especially, the dismal quality of the schools. Last year, classes in the camp were crammed with up to 90 children; of those who took Jordan’s 12th-grade exam, 3 percent passed.

The camp population has dropped to 79,000 from 83,000 in April (and 156,000 in March 2013).

While the rate of Syrians leaving Jordan has doubled to 120 per day in September from 60 in July, the United Nations High Commissioner for Refugees found that Zaatari residents are less likely to exit than those outside. Still, Hovig Etyemezian, the camp director, sees “an alarming trend” of young men selling land in Syria to finance precarious journeys to Europe.

“This is the way forward,” said a 26-year-old who left on Sunday hoping to join a cousin in Stuttgart, Germany, or former Zaatari neighbors in the Netherlands and Sweden. “I have a degree, and for five years I have not worked with my degree,” said the man, who was trained as a lab technician but has been selling stationery in Zaatari. “I want a career.”

Bassem Zuhri, 42, would love to follow him — “I wish today I could leave” — but he cannot afford $400 passports for his two wives and five children. Profits at Mr. Zuhri’s bridal shop, where poofy dresses studded with rhinestones rent for $25 a day, were slashed this summer by the $155 monthly cost of a generator.