Because it's a fun challenge. Kind of like Sudoku, but with lexan and evil geniuses.
A few ideas I had:
Dave's morse code hint could possibly be decoded as "Everything is not as it appears"(which usually refers to visual perception)
The hint is in Morse code(a communication system)
The CAD render contains a reflection, possibly of another field element(which could be considered a form of visual relay/communication)
The new control system and field elements this year will support much richer telemetry from the robot
Therefore, I'm thinking that these hints might be pointing on an increased reliance on visual feedback and robot telemetetry. However, I'm inclined to think that if this is true, the emphasis is going to be more on robot-to-robot communications and vision processing. Just plain "let's drive the robot using the camera" is not very programmatically interesting or spectator-friendly.
Looking at the hint more literally, I'm reminded of
this resturant that uses a suspended track system to deliver food to customers. Cracker Jacks and Haagen-Daaz cups or food. So maybe this is part of a system to drop game pieces down from the ceiling. Hmmm...
Or it could just be, you know, the whole field.