There's a reason for its use
There's a reason why in all 50 states it is mandatory on restaurants, church kitchens, home catering businesses that have a commercial kitchen.
It's designed to protect in the worse case scenario, that is why a good deal of the states in the united states require them.
Case histories of cross-connections whereby wastewater has travelled back into the dishwasher.
That is a common forum topic found on any plumbing/DIY'r forum. It happens and the lack of an Air Gap is why it happens.
High looping is the same as throwing a hose over the edge of your swimming pool and draining it; Once the momentum starts, it has the capability to reverse the flow other than its intended direction.
When a Air Gap leaks, the device isn't defective, it's the pipes leading from the Air Gap that causes the issue.
Here soon I'm going to find out the regulations for these devices in every state and post them. Kentucky has enforcement of these and have been for years.