Apple dictate what is inside their App Store. Along with tools that partly support the Game Development. i.e Development of Metal and their Custom GPU ( At least that is the way Apple likes to formalise their argument in court ) . In reality there is no different between the role of Apple and Sony when viewed from a business perspective. No matter how big or small their input into Games. They take their Cut on Games purchase. So either Sony is not counted as one, and if they do the similar revenue counting could also be used for Apple.
Walmart does make money from games if they sell games, yes. That doesn't make them "a game company," but that isn't actually the question.
I think people -- on both sides of this little mini-debate -- may be trying to carve out too fine a distinction. Insisting that it's only correct to say that a company makes money from games if the company is developing or publishing games suggests that GameStop doesn't make money from games -- a rather hard position to defend.
The reason why Walmart or GameStop wouldn't be counted in Game Revenue is because they belong to Retail segment. Even if they were to be counted I think retail label would have to be inserted somewhere.
Neither Walmart or GameStop contribute anything to the actual making of Games. They have added zero value to the making of Games in that value chain and act as distribution only ( and arguably discovery in terms of foot traffic ). Since Retail is a clearly defined term, It is perfectly valid to suggest ( Apple's ) App Store as similar to Walmart and GameStop. But I dont think anyone would agree Apple == App Store. Apple as a Platform ( providing tools and support ) Apple as a Publisher ( Buy apps from you and resold to their customers ) and Apple as a Distributor ( App Store ).
It is all about the value creation and where the cuts are taken. It is also the reason why most of the debate about Apple becomes pointless where these aren't clearly defined in the argument. Although Judge Rogers seems to be able to dissect all of these in a very clear manner.