I never quite understand why Blizzard went down the path of allowing players to buy Loot Boxes with money. While I obviously do (it earns them loads of money in Overwatch), there's no mistaking that it's a dubious practice that's a cancer on videogames. It preys on those susceptible to gambling, and doesn't actually encourage play - just purchases. It looks like Blizzard is trying to steer its practices away from such behaviour, and recent notes suggest it'll come soon. 

• Loot chests are no longer available for Gem purchase
• Rare loot chests are now available for Gold purchase (3000 each)

With Loot Boxes disabled in Belgium due to the fact it's unregulated gambling, I think it was only a matter of time before Blizzard changes its monetization model. Full notes here.