From a legal perspective, Apple's biggest concern, by far, is that this case could set a precedent for using courts to sanction Apple without letting Apple in court. Next to that, revenue is meaningless. Because they can take your revenue from whatever source via judgement, without giving you so much as an opportunity to file a brief in front of the court.

This is one time where there is much more on the line than money. At least for Apple. Maybe for everyone if the Supremes were to say this is OK. (Unlikely in the extreme, but still.)