yeah, that is true, if it did indeed happen that a 250 bag lot was allowed to enter and won (I think there is a current max limit of 150 bags, but don't quote me on that) then the auction price would likely be lower than if the same coffee appeared as a 15 bag lot. Scarcity definitely plays a role. There is a handful of roasters worldwide who have been the traditional buyers of top 5 lots, and most of them are relatively small. When they are forced to compete with each other to acquire the top coffees you end up seeing these record prices.
We were in the running for that Brasilian coffee and dropped out at the end because our group started to atrophy once the price broke 40 bucks.
As a buyer, I can go out and get a couple of bags for sky-high prices and be fairly confident that we will sell them and recoup our costs. But I would surely struggle not to lose money if I had to try to sell 100 at such a high price. I think the industry is still a few years away from that.
There are other things that affect auction price as well---in CoE auctions with fewer offerings (ie, 18 as opposed to 28 coffees) there is normally heavier competition and higher prices.
When the competition is underway, there is no knowledge on the part of the jurors about what the lot sizes are. The best coffee wins, no questions asked. You could run stats on the 25+ CoE auctions that have taken place and probably come up with an range of quantity (say 15-23 bags) that would maximize earning potential given a high ranking in the competition. There are several variables, of course, but one could probably come up with a formula of sorts.
But there are more bidders every year, and this will have an impact. As CoE gains commercial recognition, the formula will shift due to the influx of new buyers with different resources and agendas. On average it is much more expensive now to get these coffees than it was three years ago.
Looking at it from the perspective of the farmer, one should also consider gross profit...is it better to sell 15 bags for $20.00 and 235 for $1.50 or sell 250 for $4.00?
Speaking on behalf of the Small Axe group, I'm very certain that most of the members would be thrilled to get 50+ bags each of a smoking hot competition winner for $4.00/lb, and this would work to the advantage of the aforementioned theoretical farmer.
Either way, the CoE is about much more than auction profits. The most important goals are better market awareness as regards quality (as much on the industry side as the consumer side, or perhaps moreso), the celebration of the farmer, the advancement of cupping skill at origin, the promotion of unheralded appellations/growing regions within a country, etc. Maybe the best accomplishment of the program is the connections that are created between specific roasters and specific farmers--people who otherwise may have never become acquainted. Farmer A has great coffee and Roaster B wants great quality--but how do they find each other? CoE works brilliantly for that.