I don't think its as clear cut as are you going to die without antibiotics. I and I think everyone pretty much believes they are over prescribed.
However you have to consider that most of us are not living in sparse populations with infrequent travel anymore. Its not like if you are sick you can do the minimal work to keep the farm running and for go that trip into town for a couple weeks while we convalesce.
Most folks have jobs they have to be at with only an handful of sick days and they have to go to shared grocery stores, many might use public transportation, children go to school, etc. If you don't treat them they will have higher levels of infection longer, and are more likely to infect others. More people infected means more bugs out there total, which probably also means more mutations and more potential for a really virulent strain to develop as well.
That is one of the concerns with the Ebola outbreak right now, there is concern that if some intervention does not arrest the total number of infected individuals it could evolve into something airborne and we may find a really uncontrollable plague on our hands.
So there is probably some fuzzier line the medial professionals will have to draw. As a lay person I can't say much more than its probably NOT a good idea to keep passing them out to healthy livestock. Doctors should probably stop giving them to kids they think have viral infections just to make parents feel like they are doing something, but perhaps if they feel it might prevent a complicating infection maybe they still should. We probably should continue to use them on people and pets when we believe the infection is bacterial; but really impress on patients the need to complete the therapy and ensure that the colony is completely wiped out.