Hi Eon:
You're right about so many positive attributes that could be commented on.
For the field trip, students get out of their comfort zone and for some, maybe even for the first time, begigin to realize some of the realities that'll be coming their way as they progress in the profession. Could be a little scary.
But more often, I think some student get really jazzed from the field trip experience. Realizing they will soon be a part of this profession. Motivated? You bet! A vision of a potential career that will brig happiness and satisfaction to someone who has not experienced that in the past can be a very powerful inspiration, which can lead to better class performance, focus, attention, and participation.
I'll take that any day!
Regards, Barry