PORT-AU-PRINCE, Haiti—The lights of the casino above this wrecked city beckoned as gamblers in freshly pressed clothes streamed to the roulette table and slot machines. In a restaurant nearby, diners quaffed Veuve Clicquot Ponsardin Champagne and ate New Zealand lamb chops at prices rivaling those in Manhattan.

A few yards away, hundreds of families displaced by the earthquake languished under tents and tarps, bathing themselves from buckets and relieving themselves in the street as barefoot children frolicked on pavement strewn with garbage.

This is the Petionville district of Port-au-Prince, a hillside bastion of Haiti's well-heeled where a mangled sense of normalcy has taken hold after the earthquake in January. Business is bustling at the lavish boutiques, restaurants and nightclubs that have reopened in the breezy hills above the capital, while thousands of homeless and hungry people camp in the streets around them, sometimes literally on their doorstep.

“;The rich people sometimes need to step over us to get inside,”; said Judith Pierre, 28, a maid who has lived for weeks in a tent with her two daughters in front of Magdoos, a chic Lebanese restaurant where diners relax in a garden and smoke flavored tobacco from hookahs. Chauffeurs for some of the customers inside lined up sport utility vehicles next to Pierre's tent on the sidewalk near the entrance.

Haiti has long had glaring inequality, with tiny pockets of wealth persisting amid extreme poverty, and Petionville itself was economically mixed before the earthquake, with poor families living near the gated mansions and villas of the rich.

But the disaster has focused new attention on this gap, making for surreal contrasts along the streets above Port-au-Prince's central districts. People in tent camps reeking of sewage are living in areas where prosperous Haitians, foreign aid workers and diplomats come to spend their money and unwind. Often, just a gate and a private guard armed with a 12-gauge shotgun separate the newly homeless from establishments like Les Galeries Rivoli, a boutique where wealthy Haitians and foreigners shop for Raymond Weil watches and Izod shirts.

“;There's nothing logical about what's going on right now,”; said Tatiana Wah, a Haitian planning expert at Columbia University who is living in Petionville and working as an adviser to Haiti's government. Wah said the revelry at some nightclubs near her home, which are frequented by rich Haitians and foreigners, was now as loud—or louder—than before the earthquake.

The nongovernmental organizations “;are flooding the local economy with their spending,”; she said, “;but it's not clear if much of it is trickling down.”;

Aleksandr Dobrianskiy, the Ukrainian owner of the Bagheera casino here in the hills, smiled as customers flowed in one recent Saturday evening, drinking Cuba Libres and plunking tokens into slot machines.

He said business had never been better, attributing the uptick at his casino to the money coming into Haiti for relief projects. That spending is percolating through select areas of the economy, as some educated Haitians get jobs working with relief agencies and foreigners bring in cash from abroad, using it on housing, security, transportation and entertainment.

“;Haiti's like a submarine that just hit the bottom of the sea,”; said Dobrianskiy, 39, who moved here a year ago and carries a Glock handgun for protection. “;It's got nowhere to go but up.”;

Sometimes the worlds of haves and have-nots collide. Violent crime and kidnappings have been relatively low since the earthquake. But when two European relief workers from Doctors Without Borders were abducted outside the exclusive Plantation restaurant this month and held for five days, the episode served as a reminder of how Haiti's poverty could give rise to resentment and crime.

The breadth of Haiti's economic misery seemed incomprehensible to many before the quake, with almost 80 percent of the population living on less than $2 a day. A small elite in gated mansions here in Petionville and other hillside districts wields vast economic power.

But with parts of Port-au-Prince now in ruins, tens of thousands of people displaced by the quake are camping directly in the bulwarks once associated with power and wealth, like Place St.-Pierre (across from the elegant Kinam Hotel) and the grounds of Prime Minister Jean-Max Bellerive's office.

The city's biggest tent camp, with more than 40,000 displaced people, sprawls over the hills of the Petionville Club, a country club with a golf course that before the quake had its own Facebook page for former members. (”;Had the best Citronade; I bet I drank thousands of them, no exaggeration,”; one reminiscence said.)

Petionville's boutiques and restaurants stand in stark contrast to the parallel economic reality in the camp now at the Petionville Club. Throughout its maze of tents, merchants sell dried fish and yams for a fraction of what the French cuisine costs in exclusive restaurants nearby like Quartier Latin or La Souvenance.

Manicurists in the camp do nails. A stylist in a hovel applies hair extensions. The camp even has its own Paradis Cine, set up in a tent with space for as many as 30 people. It charges admission of about $1.50 for screenings of “;2012,”; the end-of-times disaster movie known here as “;Apocalypse.”;

“;The people in the camp need their diversion, too,”; said Cined Milien, 22, the operator of Paradis Cine.

Still, a ticket to see “;Apocalypse”; is a luxury out of the grasp of most people who lost their homes in the earthquake. Some of the well-off in Petionville who have reopened their businesses have done so cautiously, aware of the misfortune that persists on their doorstep.

“;It's kind of hard for people to dance and have fun,”; said Anastasia Chassagne, 27, the Florida-educated owner of a trendy bar in Petionville. “;I put music, but really low, so like the people walking outside the street don't hear, like, 'Hey, these people are having fun.”;'

Not everyone in Petionville has such qualms. Dobrianskiy, the casino entrepreneur, said he was pleased that Haiti's currency, the gourde, had recently strengthened against the dollar to a value higher than before the quake, in part because of the influx of money from abroad.

And on the floor above Dobrianskiy's casino, a nightclub called Barak, with blaring music and Miami-priced cocktails, caters to a different elite here: U.N. employees and foreigners working for aid groups. They mingle with dozens of suggestively clad Haitian women and a few moneyed Haitian men taking in the scene.

As hundreds of displaced families gathered under tents a few yards away, the music of Barak continued into the night. A bartender could not keep up with orders for Presidente beers.

“;Those who are gone are gone and buried, and we can't do anything about that,”; said Michel Sejoure, 21, a Haitian enjoying a drink at Barak. Asked about the displaced-persons camp down the street, he said, “;I would want to help but I don't have enough, and the government should be the ones that are actually helping these people out.

“;But,”; he said over the booming music, “;they're not.”;

Grant Fuller contributed reporting.