Have you looked at a ZIF socket?
All the ones I've seen are too tall to be able to use a shield if
it were used on an arduino board.
For about $3 you can get a USBASP ISP programmer and program any chip in place without a bootloader.
And anybody that needs to burn multiple chips can build up a rig to do this.
You could use your existing arduino or any ISP programmer
then solder a zif on a board like this:http://evilmadscience.com/productsmenu/tinykitlist/74-atmegaxx8
or easily make your own board to hold the socket. There really isn't anything to it.
You could also buy shield kit like this and use your Arduino or an ISP programmer:http://evilmadscience.com/productsmenu/tinykitlist/253