Earlier quoted context omitted.
Shouldn't the developer have known this through reading the rules of the store BEFORE he/she developer the app? If you can't be bothered to do due diligence before making such a big business decision you aren't equipped to run a business.
As the article pointed out, Google currently features a free app that offers IAP using PayPal. Perhaps the developer did do their due dilligence and saw that Google is (supposedly) OK with it.
He mentions it's a 'similar' process. Maybe there is a crucial difference in the way they are handling things. Hard to tell though as he doesn't mention what the other app is. Still my point stands. If you are breaking a rule because someone else has got away with it you are taking a big risk.