I suspect that your analysis is completely wrong. IANAL, and all.
1. Apple disallows in-app purchases for physical goods; presumably this would include services that are provided in the physical world instead of wholly electronically.
2. Apps have to be (minimally) useful to people without requiring a for-pay subscription.
3. These new rules would only kick in if you offered content (or possibly services; this is the SaaS question still unanswered, but it probably only applies to content as delivered content—that is, it seems to me to not apply to rental content, e.g., Netflix or Hulu) to people that is dependent on a subscription fee or a one-time fee.
As an example, let's say your wife's app were to have two news feeds about her fitness bootcamps (regular and premium). If all of her fitness bootcamp clients (the people who pay $200) are given access codes to the premium feed subscription, she may be required to offer in-app purchase of access to the premium news feed to people who are not or cannot be her physical customer at a price equivalent to or less than what she charges for the physical customers to have access to that feed.
All you'd have to do to comply is provide access to the premium news feed as an in-app purchase for $200 or less and let Apple take 30% of that. They're not getting anything for her fitness bootcamp services.