This week I had the opportunity to use the GE kiosks for the first time (new Nexus/GE member). As I was bringing cheese back from Europe, I marked the food question with a 'yes.'
To my surprise, I did receive a big 'X' on my slip, but rather a large circle around the words 'proceed to baggage inspection.'
I ended up spending about 20 minutes in secondary, with the agent typing away my reason for travel (a Mileage Run, where I only spent 24 hours on the ground). He also inspected my bags.
This would probably NOT have happened if I had waited in the non-existent line, and spoke to a CBP officer. So, so far, GE actually hurt me more than it helped me...