The pricing is not the point, but since you asked:
1. Most apps (> 99%) in the app store don't make any money (many don't even charge any money). So Apple is already doing it for those folks for $99/year.
2. Even if they had to charge more per year (which I don't think they do), i would still prefer this model. Heck, Apple could still take a percentage (though that makes distribution a bit more complicated), just as long as other app stores have some margin to work with. Another way to handle is to have devs pay per review. Apps that have a lot of churn would pay more.