Why are games on WP8 more expensive?

I'm honestly confused about this. If WP8 is looking for more of a marketshare wouldn't it make sense to price their apps lower. Yet tons of the apps (especially games are more expensive then their iPhone and Android counterparts.

Ex:

WP8 Price iOS Price

Centre jour: 2.99 0.99

Asphalt 5: 2.99 0.99 (for Asphalt 7)

Battleship: 2.99 0.99

Gravity Guy: 2.99 Free

iStunt 2: 2.99 0.99

Doodle Jump: 2.99 0.99

I'm thinking of jumping ship to WP8 and for a majority of folks, something that's holding them back is their ecosystem. We would have to buy our apps again if for example switching from the iPhone. And then on top of that you make top games even more expensive. This would act as a serious deterrent.