When I was a communication major in college I had a professor that also taught health care communication. She said the hardest thing for pharmacy workers to learn was the customer service side.
Apparently working in a pharmacy exposes a lot of workers to the most upset of the upset. You have people angry because of the price of medication, people blame you for insurance snafus (I've done this when I was upset, I'm not proud to say) and very sick, agitated people in general.
So customer service skills are a must and you have to be great at dealing with angry people.