If you want people to approve notifications don't just throw up a permission dialog at startup, let them use your app for a bit, and when they make an action that will cause notifications to be needed ask them then after telling them why you want to use push.

Saying "you can just delete the app" seems to be missing the point somewhat. There are many games that I enjoy playing, but I don't want them sending me a message about having a free coin while I'm trying to sleep.