IPhone app review shakedown

Maybe I'm missing something here, but where's the shakedown?

1. It's $20. In every company I know you can give and accept $20 gifts from clients and customers without it being considered a bribe.

2. Paying $20 to have a link to the app store at the bottom of a review is good value for money. It will encourage impulse purchases, and it doesn't cost the review site anything.

3. The email explicitly states that the $20 don't affect the review process. So you're not paying for a positive review. Why would the review site risk their reputation by asking for $20 bribes?

4. You can just say "no thanks", so it's not a shakedown.

Geez, people.