Under Australian Consumer Law (specifically the Australian Consumer Law, which is Schedule 2 to the Competition and Consumer Act 2010), it is illegal for EB Games, or any retailer, to sell a pre-owned or used game as "new." This would be considered misleading or deceptive conduct, and a product must match its description.
A "new" game should be in its original, sealed packaging, unused, and with all original components. If they are selling a pre-owned disc with a booklet in a generic case, it must be clearly and prominently advertised as "pre-owned," "used," or "second-hand." If you were sold a pre-owned game that was presented as new, you have grounds for a refund or replacement under your consumer guarantee rights.
It's always a good practice to clarify the condition before purchase and keep your receipt. On a different note, while digital card games like
Royally Rummy Yono don't have physical condition issues, understanding your rights as a consumer is equally important for all purchases.