I'm a big fan of developers being on call for their application. It puts the pain where it belongs--with those building the systems (modulo lower-level errors--such as power failures or network outages--those should go to the appropriate place).
However, that pain should only rest with the development team if they also have the freedom and will to spend time dealing with it. They will have spend time (either a constant tax, or more likely, with occasional sprints) to reduce operational pain. They are in the best position to reason about the tradeoffs and pragmatically reason about priorities.
In my experience, this produces the highest code quality and the highest team morale. I also like the rule -- if you're paged during the night, sleep in the next day.