Ponzi Beach Juice?

What would you do if, hypothetically, you were on a beach, when, through the Public Announcement system a clear, yet polite and restrained, voice announced in an inviting tone: "time for the next round of the big challenge! Come on everyone, let's line up for a chance to win some special prizes!" ?

Now, you may think that this is just a figment of an overly exercised imagination, or another frothing hallucination, but no, this actually happened in Shirahama ("White Beach"), the overlooked coastal jewel of Kansai (for those in the back of the class, that's the west bit of Japan).
So, within the time it would take the average well-fed European male to fold up, nay - to get up from, a deck chair, a well-ordered and perfectly-formed line consisting of a great multitude of children sprung up, as if they had appeared out of the sand.



But not only children answered the call. Here, an adult is trying the challenge. You need to win in paper-scissors-stone (a standard dispute resolution tool in Japan, possibly why no one ever gets angry in public).
One round is best of three against the athletically-uniformed staff, but - you need to win all three rounds to get...

... a carton of juice! However, there are only a very limited number of cartons to win!

And this, I feel, reminds me a little of the market. The path to success is laden with challenges. Oh yeah - and be wary of a crowd. And, if there are a lot of folks chasing a limited amount of assets, then be careful - the juice may run out, or it could be a Ponzi scheme.