These 'mystery boxes' thing are super common in the gaming world. There are many websites in which you can bet money to open a mystery box containing a game, or in case of some games a skin for the game's weapons.
The websites themselves are very manipulative. First of all, many offer a "test spin", which usually gives you a very good prize just to lure you in. Secondly, they use popular Youtube personalities to perform "box opening" videos, they get e.g. 30 free box openings. What isn't told, is that it's trivial for the mystery box website to boost the winning chance for the youtuber so that people think "wow, it's so easy, I can win that too". Thirdly, when doing the spin animation, they usually show you that the prized possession you were after was just around the corner, you were very close. Just give it a one more spin, you'll surely get it this time!