The buses shown in the game have doors on the right side, for right-hand traffic. Traffic in Australia is on the left-hand side; the game's other vehicles correctly reflect this.
The constant use of the word gas to refer to petrol, aka Gastown.
It is a purely American (USA) thing to refer to petrol as gas; in all other areas of the world and certainly in Australia the convention is to only say gas when referring to LPG.
The Mad Max series is supposed to be set in (or around) Australia and the right-hand drive vehicles used in the game further emphasise this, thus its a fairly huge language error.