I don't understand why manufacturers are trying to solve problem for user. User has power uninstall app that is draining battery or replace it with something else. There is rating and comment section in app store exactly for this. What they could do instead is to display warning that app is using too much battery, but they SHOULD NEVER KILL AN APP. It may sound radical, but only countermeasure we developers have is t…
The user experience is more important than a app developer's need. Users want better battery life. They don't want a app using it up. Feel free to block the installation of your app on devices that you feel unfairly target background apps, they'll just use a different application.
Everybody wants better battery life, but also their alarm app to wake them up, or tracking app to record their runs in the background, receive notification when there is new email or im message, etc. And these functionalities get disrupted by excessive battery management (killing apps in the background).
Somebody thinking he knows what users want and making decision based on this assumption (without really asking user) is exactly what brought us here. We are not all the same, somebody can have bit different priorities then you.