Enjoy your towel, sir!

i have always been curious to understand the training programs that some industries have.
in some five star restaurants, i wonder why the trainees are made to wear shining brass badges that say 'trainee'. it makes me nervous when trainees bring or take glasses of water or soup, precariously balanced on their hands.
maybe it is to ensure that the guests are more understanding when they see a trainee.

as part of that training, they are also trained to make some small conversation - such as
? how are you today?
? did you have a good day at work?
? enjoy your meal!
i can understand that.
one of the airlines that i regularly travel with, even has a question in their passenger feedback form - whether one was greeted on entry into the aircraft.. making it explict that it is a standard instruction to repeat the welcome greeting for every person boarding.

recently, a trainee steward [the cabin crew normally does not wear the trainee badge ], but i could sense that this person was new to the job - by the enthusiasm displayed to please every passenger.
while serving snacks, he made sure that everyone was wished - enjoy your meal, sir / madam!
while distributing the cold towels to freshen up, he said - enjoy your towel, sir!
to me, that is the limit...