I've been to tech conferences in San Francisco (Moscone specifically), Vegas, Orlando, Chicago, and Boston. While I'm not ordinarily a fan of Las Vegas, it is hands down the absolute best place for conferences, logistically. It's a 10 minute Uber to get from the airport to the strip. Tons of hotels on the strip. If the conference is at one strip hotel and you are staying at pretty much any other strip hotel, you can…
Large crowds. Everything hotel/conference room smells like smoke (terrible for asthmatics). Lots of distractions that are especially bad for those with addictions.
If I'm at an event for work, I don't want those things. I want an event that keeps me focused and engaged with the material and the connections.
When a conference is held in Vegas, I know it's going to be more of a party than an educational experience, so I tend to write it off simply because of the location choice.