Assigning Fee (Officials or Schools)?

[Valley Man]

Had an interesting question posed this week and wanted to get some feedback

1. What is the "assigning fee" for the games you work?
Our association is 6% at the end.

2. Do the officials or the schools pay this "fee"?
Our association, the 6% comes out of the final official's check.

So why do the officials pay the assigning fee and not the schools pay that fee?