It's a little bit humorous to look back on this one...
When I was still a hyper-conscientious newbie JW, I once applied for a server position at a restaraunt. I just about had the job, but in a phone conversation with the manager, I asked if I would be expected to sing "happy birthday" to my customers. She was a little surprised at the question, and said that they do have a customary thing they do when a customer is there celebrating a birthday. I proudly told her that as a JW I couldn't do this. She said that she would look into it and call me back. She called back the next day and said I'd do better to keep looking for a job. The whole thing was kind of embarrassing really. She thought it was so weird. And it was.