Mcdonald's announced that its Monopoly promotion is coming back this year. Mcdonald's ran its first Monopoly-themed promotion in 1987. You'd collect scratch-off tokens corresponding to different properties on the monopoly board. Different menu items would yield chances at different property tokens or an "instant win" for something small like a free coffee or fries.

If you matched all properties in a color set (e.g., Illinois Ave, Indiana Ave, and Kentucky Ave), you'd win a grand prize.

The chances of acquiring any property are about 1 in 11 — except for one piece of every set. The chances of pulling the rare piece in these sets range from 1 in 450,000 (Mediterranean Ave, $50 gift certificate) to 1 in 450,000,000 (Boardwalk, $1 million).1

These types of games are called Complete Gacha (Kompu Gacha) and were so popular in Japan that they are now banned. There are variations of the Gacha game –

Loot boxes are another form of Gacha games that show up in video games. Roblox is one game where a significant portion of games are play-to-win with loot boxes.

1Probabilities from the 2014 game – source.

2Your real chances of winning the grand prize from 1989-2001 were zero – if you didn't know "Uncle Jerry". He was the chief of security at a subcontractor that McDonald's used to run the promotion. "Uncle Jerry" was secretly stealing the winning pieces and distributing them to his friends and family. Eventually, the Mafia got involved. There's a documentary on HBO about it called McMillion$.