The 2 clubs for whom I am treasurer have the same system. After the event, the Event Secretary sends the treasurer a list of all scratches with notations 100%, 50%, or 0 refund. The determination is based upon the wording in the premium:
"A full refund will be given for entries withdrawn prior to the closing date. A full refund will be given for death of a dog, bitches in heat, and for an injured dog (with veterinarian certification). A 50% refund will be given for other scratches, but only if notification is given to the Event Secretary or stake marshal prior to the start of the stake."
This wording seems to answer any questions.
Car trouble. Company from out of town. Dog not ready. Too hot, too cold, it's going to rain. The refund will be 50%, but only if you contact the Event Secretary or stake marshal prior to the stake. Otherwise, you are a no show and get -0- refunded.