But do those games let your 11-year-old nephew drive you to school in his favorite car? Didn't think so.
Ultimately, I've learned that the secret to Roblox's success is no mystery. It provides an endless stream of new and novel experiences that you can enjoy with your friends, on every device. It's a cross between "The Matrix" and your favorite neighborhood park.
Robux can also be used to customize your avatar. I'm a scrub, so I'm rocking the default options. But everything from wings to helmets to armor are on the table, for ballers who aren't me.
Popular games like "Roblox High School" and "Work In A Pizza Place" have also spawned Roblox-branded toys, which come with virtual in-game items. Roblox games are slowly becoming cultural forces in their own right, and developers get a cut here, too.
Popular games earn a dedicated player base, however. Games like "Meep City," for example, lets players ride a Segway if they spend 60 "Robux," an in-game currency you purchase with real money. Roblox itself splits the revenue with the game's creator, which is how those millionaires get made. For what it's worth, my nephews have never spent a real-world dime on Roblox and still have a total blast.
Importantly, every game is multiplayer, and a friends list feature makes it easy to play in a group. And because every Roblox game is free to play, it's easy for the whole crew to roll from game to game.
So what makes it so sticky? Well, first off, you gotta think about Roblox as a social network, too. It's available for PCs, tablets, smartphones, and the Microsoft Xbox, so pretty much anybody can play.
There's seriously a dizzying array of games available for Roblox. Some of them are really creative, like this loving tribute to the Pokémon games, called "Pokémon Brick Bronze."
And this is "Jailbreak," a cops-and-robbers game that can have as many as 75,000 simultaneous players. A lot of these games are fairly simplistic, but "Jailbreak" sets itself apart with complicated mechanics for escaping jail and going on a crime spree.
This is "Murder Mystery 2," which focuses more on the "murder" than the "mystery." Tony derides the knife they give to new players, and helpfully offers to lend me a better one that he earned through playing.
Another curious property of these games is that attending classes in a virtual school is a big part of the experience. One or more players gets to be the teacher, and the rest sit in class until time is up. This part makes me feel very old, because back in MY day, I played video games to forget school even exists.
This is Tony's house, with Diego sitting next to me on the couch. Tony is very proud of his house. On one visit with Tony, he was sulking because he had spent all his virtual money on a house in the similar "Roblox High School."
"Meep City" is pretty typical of a lot of the Roblox games I've played. You pick a character, dress them up, and generally just hang out with other players. And yes, I'm dabbing here. I mentioned this is popular with kids, right?
There are lots of different types of games, and not all of them are bang-bang-shoot-em-up. For instance, Diego and Tony are big fans of role-playing Roblox games like "Meep City," pictured here.
And making Roblox games can be really lucrative. Both of the 18-year-olds pictured here are top Roblox developers, and both have already made enough from Roblox games to finance their college educations.
So what makes Roblox so sticky and addictive for kids? First thing you have to know is that Roblox is much more like an app store than it is a game in its own right. By using Roblox, you can access games in pretty much every genre imaginable.
This is Jailbreak, currently the most popular