Back when medals had to be "approved" they would not have awarded this many medals to one event for the reason tc stated. If I remember correctly, there were never more then 3 medals awarded to non-alliance events. If it is easier to get a medal they have less value, they, or really it was Chachi, wanted to keep medals prestigious. If you remember, there was even a minimum participant number required to have medals awarded to an event, for example.
I'm not trying to change your mind, I'm just giving my opinion. I'm grateful you took time to put on the event and it was a good time for all.
I'm just for keeping the medals as a tough accomplishment.