Well, since you only ever only submit the compiled application binary to Apple, it'd be pretty darn hard for them to detect behaviour like this. Especially if the code to do so is obfuscated, and/or the data is smuggled out via SSL (or worse, steganography-style piggy-backed on to other data).
Sometimes it's tempting to speculate whether the real purpose of the app store review team is just to ensure developers aren't trying to access Private Frameworks (i.e. non-public APIs) or try to upsell the customer while bypassing the 30% Apple tax?
Sometimes it's tempting to speculate whether the real purpose of the app store review team is just to ensure developers aren't trying to access Private Frameworks (i.e. non-public APIs) or try to upsell the customer while bypassing the 30% Apple tax?