When I first began selling shoes in Second Life, I made them Transfer OK, since that reflected the way that we use objects in RL. But over the years, many people asked me to make Copy OK versions, because if you keep outfits in Folders (which makes it much easier to switch from one look to another), then you need to be able to make multiple copies of the shoes.
For those people who want to buy shoes as gifts, fear not! In the entrance to the store is a Transfer OK vendor. If you want to send Copy OK shoes as a gift, please contact Cobbler-in-Chief, Eponymous Trenchmouth