Pricing

I have just been thinking about the issue of how to price pottery (or any other art / craft for that matter.
It has come to my attention that recently; a plate of mine was entered into a fund raising auction where it fetched 3 times what the original purchaser paid for it. I have also put items into these types of fund raising auctions where they generate between 3 and 6 times what I feel is a fair retail price.
My belief is that this jump in what people are paying is due to the fact that they are supporting a good cause, and are getting something as a “bonus” for donating money. I have been told that if people are buying these items for a greater amount than what I am charging, then I should increase my prices to reflect this. That would be nice, in theory…however, I think they are priced accordingly, and in all honesty, I could not ask someone to pay over $100 for a small 13” plate. I think people should be able to afford this art form, and to price it out of the “every day person’s” budget is, in my mind, a little greedy. Now, I don’t have a problem charging a higher price for something that is extra special that came out of the kiln with just a bit more pizzazz that was expected, or that I spent 20 hours working on as opposed to 1 or 2 hours. For instance, I charge between $15 and $20 for a cereal bowl, but $20-25 for a coffee mug. It takes longer to make the cup, even though it may be the same size or smaller than the cereal bowl.