I assume that Apple's IP lawyers knew about this patent when they were researching about in-app purchases. Morally right or wrong, why didn't they just license it then? Patent trolls are one of the few groups of people I'd rank beneath telemarketers on the scum of the earth scale, but they are a known quantity and can be avoided for much less than the settlements they ask for later. Especially for a company with a multibillion dollar IP fund like Apple.
Don't be so sure that Apple knew about this. There is a school of though on doing patent research before developing a product. It says do no research. That way, if you are sued and loose, the infringement can not be views as willful - which would treble the damages.
