They are still over prescribing, and it is partly cya medicine (like someone with a sprained ankle getting an MRI when it is pretty obvious it is a sprain) and partly the doctor wanting to make the patient feel like they can do something for them. With viral infections, the reason given is often that the antibiotic is to prevent bacteriological infections from happening because the body is fighting off the viral one, and I kind of find that dubious. Among other things, antibiotics can wipe out the bodies own immune responses if I remember correctly, and because they tend to wipe out the ‘good’ bacteria we rely on in our gut, it further weakens us since we rely on that gut bacteria in digesting food. When I talk to people I know who get some sort of viral respiratory infection going around, it is very common for them to get a prescription for antibiotics. And yes, sometimes if they don’t know what the person really has, they will give a broad spectrum antibiotic. I remember the days @michigangeorgia is talking about, when I was growing up strep throats tended to run in my family, and when it looked like I might have it (back then the culture took like 48 hours) they immediately started me on it, I ended up allergic to penicillin because of that (in that case, I obviously don’t blame the doctor, strep throat is nasty and 48 hours could allow it to become much worse).
The results are clear, there are whole classes of microrganisms that are resistant to almost all the antibiotics out there, and that happened because of over use. And yes, the wholesale use of antibiotics in meat production, in things like fish farming in some cases, have also led to problems, in the past couple of decades to increase the growth rate of cattle ranchers started giving animals antibiotics routinely because it allows them to grow much more rapidly (and also helps ameliorate the often crappy conditions on family farms, where due to tight quarters and less than stellar cleanliness diseases spread like wildfire). I have heard the arguments from proponents, that the antibiotics by the time it is cooked are no longer present (or never were), but what that leaves out is that bacteria in the environment where this cattle are raised don’t just hang out at that ranch, they spread via the animals being transported, get into the groundwater and so forth, and those resistant bacteria breed. The last I checked (and someone on here may know more about that) the FDA has refused to ban the broad based use of antibiotics like this, but rather has left it up to a voluntary basis.
update- I checked, and apparently while the FDA has not banned the use of antibiotics like this, they (to me) did an end run, and now the use of antibioticis in animal feed requires a prescription from a veterinarian who will be responsible for its proper use (this is as of December, 2016). Doesn’t mean a friendly vet won’t gladly write the prescription, or ranchers won’t turn to black market supplies, since from what I can tell there is no one going to be checking to see if the cattle are still being fed antibiotics, that there will be no one upstream running blood screens on the cattle, and without that ranchers may be tempted knowing it is unlikely they would be caught to continue the practice…but at least the FDA finally acted, before this the last rule was a call for volunary restraint