Apparently they are signature transactions, no Ether sent, just a little gas.
https://etherscan.io/token/0xd5524179cb7ae012f5b642c1d6d700bbaa76b96b
What bothers you?
What bothers me is that I attempted to buy shares of a market on Augur and following the steps signed a message. The message cost 10 cents in Ether as gas and went to the address I cited. But no Ether was sent and Augur recorded no change in the market and my attempted purchase of Yes shares went nowhere. So I'm just wondering what happened, and why so many other people apparently did the same thing. I guess I'm just missing some big obvious piece of the puzzle, being (like nearly everyone) new to Augur.