How is the "Shut up and take my money" effect achieved?

Today I just remembered something Ziegler (I think) said a while back, that the iPhone got him to spend more money in 10 minutes than he did with the Droid in 2 years. And there are many charts showing that per-user, iOS apps are still bringing in more revenue.

And there was a post in Apple Core with a beautiful Apple TV concept and I couldn't figure out why, but it did make me want to spend money there somewhat.

To some extent that happened when I got the Nexus 7, but I always hesitate before I buy anything and ask myself whether the thing I'm buying is worth the money. iOS users tend to have less qualms.

What is it about iOS that burns a whole in people's pockets? What is getting people to spend so easily?

And how can Android replicate this effect?