Some Steam account holders found their account wallets literally bulging at the seams thanks to a $5 or so credit yesterday, a lump-sum windfall that no one seemed to know or understand the reason behind.
The credit arrived with no explanation, save for the reference "Valve Mastercard" alongside the payment. Which made it sound a bit like a scam to some users, who are not exactly trusting of Valve's systems or the friendliness of some users of the Steam universe.
What was really happening was quite boring. A loyalty discount to buyers of Steam's Dark Souls III and Steam Controller bundle had not been applied, hence people were getting this retroactively credited to their accounts; a fact belatedly explained by Valve once the money had appeared and the masses started panicking about it being some sort of elaborate hack involving fake credit. But it was fine. [Kotaku]