Most people don't know this thing when they go to buy the device, and of course nobody will tell you about that. If on the box there is written "THIS DEVICE WILL ONLY RUN SOFTWARE APPROVED BY APPLE", how many people would buy that? In reality most people don't know this thing.
They discover it later, when they ask some more expert friend "can you install me an app to do so, like the one you have on your phone", and you have to explain that no, you can't because Apple didn't approve it for the store. And then they understand that they made a bad choice, but it's too late.
Or when someone goes to you asking for an iOS app and you have to explain that putting it on the store (the only way they can install it permanently, even if they need it only on one phone) they will have to spend a lot of money. While with Android you just give them the .apk and you are done. And most of the time these customer will buy Android phones because it's cheaper to buy a new phone than get the app on the store.
