TMZ Sports cameras were rolling as the 12 boys -- along with their coaches and other chaperones -- walked through the airport to their waiting bus ... smiling and throwing up the peace sign.

The team -- aka the Wild Boars -- were decked out in their spiffy Adidas uniforms and carrying their equipment in cool new travel bags. They just played a friendly game in Argentina against another youth squad as part of the 2018 Summer Youth Olympics opening ceremony.

But now, it's time for some R&R in L.A. -- the team is scheduled to hit up Universal Studios in the coming days where they'll get to experience everything from The Wizarding World of Harry Potter to King Kong 360 3-D.

Of course, it's nothing like surviving over 2 weeks in a crazy network of caves -- but they'll probably dig it.

So, why the global trip?

The head of the Thai Olympic Delegation explained it this way -- "During the rescue operation so many people from around the world came to Thailand and collaborated to rescue them. They feel that they owe a debt to everyone."