I was active in a UU church for several years, and Pagan. In fact, it was the UU minister who turned me on to "organized" Paganism. Though CUUPS groups have not really been
thriving around here, UU churches are still generally very Pagan-friendly. There was a regular UU service at the San Jose church that opened with calling the quarters, and several members of the congregation are witches. And lately, there is a Feri group that has been holding some public rituals in another local UU church.
Any Pagan feeling lonely for their own kind might find some like-minded people in the local UU congregation.