Development studio Psyonix has announced it disabled loot boxes in its arena soccer racing game Rocket League for players in the Netherlands and Belgium due to government regulations.
Players within the Netherlands and Belgium are now no longer able to open Crates with Keys. This change is said to be due to "government regulations". For affected players loot box opening has been disabled with patch 1.61 that was released earlier today.
The Dutch Games of Chance authority, or Kansspelautoriteit, has investigated several popular games containing loot boxes in 2018 and considered many of these to be illegal. The titles investigated include PUBG, CSGO, FIFA 18, Dota 2, and Rocket League.
When random loot box content is tradable there is almost always a certain monetary value associated with that content. This is why these countries consider paid loot boxes with random content gambling.
Aside from Rocket League and PlayerUnknown's Battlegrounds, loot boxes were also disabled in Counter-Strike: Global Offensive and Dota 2 within the same regions in 2018.