I remember reading some time ago about a cinema chain that used a technique they called "bullfighter" or similar, that was designed to reduce the customer's anger by having several layers of staff handle the issue.

With each new "layer" the customer got a little less angry, until it came to a point where the customer would be in a more reasonable state, and then a solution would be provided which made the customer happy.

The dowside was that the first few staff members that had to deal with the customer would receive the bulk of the anger which I imagine wasn't fun.

But by making the customer feel like their issue was being "escalated" (even though the layers would actually be staff of the same rank), by the time the customer was sent to an actual manager, they would be more receptive to a solution.