The annual Nightclub and Bar Show came to the Las Vegas Convention Center this week, bringing in more than 30,000 industry professionals. Bars and restaurants in the U.S. are selling less alcohol, as third-party services increasingly deliver beer, wine and liquor to the home. Recreational cannabis is also pressuring on-premise alcohol sales, as state regulations prohibit bars from selling marijuana products. However, new forms of entertainment such as esports and virtual reality could help attract younger audiences to bars.