Does your wife's job include overriding a doctor's prescription for a patient? That is what these pharmacists are doing.
It is not the job of a pharmacist to decide what she will and will not dispense. If she cannot dispense ALL of the medications or drugs that are available at a particular pharmacy chain, then it is up to HER to go to work for someone else who does not dispense those objectionable drugs.
As others have pointed out, what if a PETA-inclined pharmacist declined to dispense drugs that were tested on animals? Should they have that right, and should they have the right to lecture you about animal rights?
That said, I think the pharmacy has every right to fire any pharmacist for any reason, including this one.