Consider in a connivence fee.
It is also a way of limiting the power of auction sniping and reselling. It would be very easy to set up an app that, say, bought meat priced at less than 10c and resell it at 11c. The only limit would be being online to receive the delivery from the frog. The fee makes the market harder to manipulate.
Eventually, you will be able to make a tower and sell stuff directly to people, no charge.
It's simpler than that. 3c is the minimum listing fee. It's written in the auction window. If you do list an item/lot at 3c, you will not receive any currants for the sale.
@ Lord Bacon-o, you can still make a profit flipping stacks of items as long as they sell. In your example, you buy 60 meat for 10c, for a total of 600c. Resell at 11c, and you get 614c. The 3c minimum is per auction listing, not per item. There is a little suppression of manipulation because if your margin is less than 7%, as in the meat example, you can lose all your profit if the flipped items don't sell the first time you list them.
Also there isn't any point selling anything for under 3c. You may as well drop it on the street where someone who is actually playing the game rather than running an AH bot gets the cheap item.