Well, to be fair, the first thing that many people do look for is gambling. Multiple casinos line up and down 'the Strip' where players can come in and play cards, roulette, slots, and many other games of chance. It's big enough business that local residents and companies don't pay much to the government in the way of taxes. Gambling isn't legal in most states, possibly with exceptions on Native American reservations, so Las Vegas is certainly notorious for being somewhere that you can come to do this.
For that matter, there are a number of ancillary activities and options the casinos provide. Many of them have very luxurious hotel rooms and accommodations you can stay in, with plenty of swimming, recreation, and pampering going on. You can also catch any number of famous shows ranging across many mediums and genres, be it comedians, musicians, bands, and circus acts that entertain you after dinner.
Speaking of dinner, eating is great here. Not only is there fine dining on the strip, but a number of restaurants, some of them all-you-can-eat 24/7-style diners, around town. The food here is good, cheap, and quick. Businesses in Las Vegas Nevada are high security for a reason. There are so many people that come through this city, that it would be unwise to do otherwise.
For something touristy, you might want to stop by the World Famous Gold And Silver Pawn Shop, as seen on the History Channel. Many of the items they feature on the air are for sale in the store, as are a great many other interesting pieces.
The museums of the city are not as well-known and yet also very respected for their content and exhibits. Spending a whole day in them is very possible and quite educational if you're looking for something kid-friendly. Given how the city is surrounded by mountains and serene desert, there's also plenty of sunshine and outdoor activities to be enjoyed.
