With each Revels event, there are always a number of people that state that they will not participate due to the expiring ingredients. It does not appear that this policy will change any time soon, but the Dev's did a great thing with this year's event in lowering the material costs for a lot of items. I'm still not crazy about having to buy low level items and do progressive upgrades on them when they are BtC, but lowering the costs was a good step.
I would like to see a barter system added to the event vendor where we could trade mat's of one type for another, or at the least convert mat's to chocolates. Something like 1 Spooky Almond = 5 Chocolates, or trade 3 almonds for 1 caramel, similar to the gem trade-down that we have for the Cove. In doing this, I think it would cut down on that sense of waste at the end of the event that puts some people off & encourage more people to participate.