Change does not mean refund and many people may need to refund a ticket and that may especially be the case if they are employed or are invoicing a client/customer. If the trip is cancelled, the client/customer is not looking for a credit against future travel and that is hard to account for.

Additionally, if one routinely books at the last minute, it is hardly uncommon in today's world, lower fare buckets are not available and the metric advanced of 8-10x is simply not true.