White Shoe With Red Cross Showing Up

Have you seen these shoes around Oxford in the last couple of days?  I spotted this one on the war memorial, and have seen two more hanging on the Christmas wire that runs between LUSH and River Island.  They all have this Red Cross sprayed on them with a little bit of writing, this one says, "Better Luck Next Time"

Is it an art project?  Have you seen any around the city centre, please let me know.