Why no push to change names of San Francisco, San Diego, etc.

It just kind of hit me. I'm sure there have been fringe movements, but with all of the fervor that some make over separation of church and state, why no organized efforts to change the names of cities like these?

For example, take San Francisco, which is named after the Catholic Saint Francis of Assisi.

Surely, that has to offend some people.

And, of course, we all know the origin of San Diego's name: LINK