Bonus gold for buying gold? What?

MrConway: On Wednesday we were suffering from technical issues in our World of Tanks premium shop. Due to these issues, some players who bought items or gold from the shop erroneously received additional free gold on top of their purchase. This was not working as intended and the issue has been identified and fixed.   Since it was a glitch on our side – we have decided to call it an error in your favour and all paid out gold will remain in the affected accounts.