"In the United States there are certain hotels that don't want jewelry shows at all because they're dangerous," he said. "If you couldn't have it with armed guards I'd say you have a serious, serious problem."
That's not a view widely held on the other side of the Atlantic.
"The public carrying of weapons — even by security guards and police officers — is much less visible throughout Europe than it is in parts of North America," said Keith Krause, program director of the Geneva-based Small Arms Survey, a nonprofit that monitors global views of weapons.
"Given that civilian possession of weapons is much less available, they're unlikely to have weapons because they're unlikely to be facing people with weapons."
Zakaria Rami, a union representative at the Carlton who has worked there for 16 years, said show organizers didn't formally advise police of the show. Only a few guards hired by the jeweler provided security in a hotel showroom site where the robber struck on Sunday.
"If police knew there was $100 million in jewelry, I think they would have put a patrol car out there," he said.
The show was far from inconspicuous: One-story tall, bright pink banners covered the front facade of the Carlton, one of the most famous hotels on La Croisette — Cannes' best-known seaside promenade.
Rami wasn't at the Carlton in 1994 when a gunman opened fire at the hotel, injuring a guard before making off with $45 million in jewels. That robbery prompted the city to suspend the gem shows that draw jewelers to the French Riviera each summer, hoping to catch the eye of travelers with money to burn. The ban expired years ago, and the shows resumed.