The Germans (in general) don't have a problem with knowing here their food comes from, they have an interest in what they eat and knowing where it comes from. I have been in places where they have had details of their produce on the menus in written form, so that's nothing new for them.
There is no electricity involved, the food is sent down with the use of gravity.
The food is paid for in advance, so unless you want to pay for your meal and then run away, that problem is solved.
Each table has it's own 'track', so unless someone is going to hover around your table, then stealing your food shouldn't be a problem.
All the other stuff is equivalent to what would/could happen in other places.
The food containers have secure lids, which are hard to not lock into place.
(And I guess a waiter could trip and pour your food over you too?)
The containers are labelled and are placed on the correct track, so you should get the right food.
(Then again I have had the wrong food given to me by a waiter and it wasn't exactly a huge problem)
The German's are very safety concious, I would have thought that the issues of people being hurt (as you have described..fingers caught etc) would have been dealt with.
As for staff?
Well you have a top up card to pay for the food, so I assume there is a place to pay for it.
Someone needs to clear tables, mop up spills, help those who are confused when trying to order, so I doubt the place would be devoid of people...