Evidence based medicine is providing, what is thought to be, optimal clinical practice on the basis of clinical research and sysatematic reviewing.
And precisely for this reason, surely patients should feel 'at ease' that they are being treated according to previously tested and reviewed interventions.
If a patient enters the doctor's room, they expect a diagnosis with associated treatement, and by following guidelines produced by EBM, the patient feels re-assured that they are being managed correctly.
EBM comes with even more benefit specifically for those countries with no working framework or guidelines, EBM can bring routine and a solid basis on which to treat patients. It provides a good 'algorithm' to follow with known results.
By using EBM, you are advocating the most 'up to date and safe medical practice, and with specific guidelines to follow there is the added benefit of health care cost reduction, for e.g. as doctors will not be prescribing wasted drugs, or patients will not be sent for unnecessary tests.
Lastly, If you have and know there is good evidence available for a particular patient with a disease, then would it not almost be unethical, to ignore/avoid the EBM with regards to interventions for that patient?
