People want an answer when they go to a provider. So, they expect something given to them. Some providers will give them to everyone regardless of if it seems bacterial or viral.
The problem with this is that when a doctor prescribes you an antibiotic, most people don't take it to as a precautionary measure to think about. They take it as if the provider is saying, "YOU NEED THIS! TAKE IT!", so they do.
Providers are not incentivized to NOT prescribe either.
No really good answers.