The user would have to be aware of streaming audio. Also, as stated elsewhere in this thread, apps don't normally run in the background on Android either. I'm curious what app you believe killed your battery life in the background? That sounds... unusual.
Apps normally run in the background all the time in Android. I know which app it was (meebo) because I can view the stats afterwards. Also, to help alleviate some of your confusion, we are talking about background processes, not just streaming audio.
Apps only run in the background if they specifically register a background service. Usually this is when you click a button in the apps preferences like "update in background", etc.
