#17 die Frage, was "duckie" wohl bedeuten mag
"Duckie/ducky", or just "duck" or "my duck" is simply a term of endearment.
#12 die - zum Glück nur ein Mal erlebte- Anrede durch eine Kellnerin mit "duckie"... - dabei trug ich Jackett und Krawatte -
I don't think you should have been offended by this. I'm sure the waitress used this term to everyone, male or female, young or old and regardless of how they were dressed. There's nothing personal about it, and it's meant in a friendly way.
The other day I was in a supermarket, down here in the South-East, and a young man who worked there addressed me as "my love". (Just to be clear, a man will only use such expressions to a female customer.)