I am sure we have readers who did wait staff jobs at some point in life. I discussed the skills involved with somebody this weekend. We laughed about two topics in particular. First, how to load and balance a full tray of plates and silverware, get under it in a squat, and lift. Second, how to load a tray of 20-30 glasses and throw a damp towel on top to glue them together.
Of course, the dramatic moments are when you drop a fully-loaded tray because some little kid scurries in front of you. Big crash, everybody has to rubberneck. Good times.
Just busing tables at large events quickly and efficiently is a skill. Delivering food to the tables is another skill. When I was in college, we figured 40 wait staff for 1000 guests, 4-5 for 150 guests. It's a work-out.
Always tip wait staff. Always, in the US anyway.