Nature journals offer double-blind review
nature.com
nature.com
I'm usually a sub-reviewer, not usually on the program committee. And some of the conferences I review for are general enough that I may get papers in my general area, but not my current focus. So it may not make as much of a difference for the program committee of a tightly focused conference, but it may for all other cases.
Going through the motions and pretending that this is truly double-blind may introduce even more peculiar biases than existed if they had merely chosen to make it single-blind.