Hi April, I'm from Seattle and both cities are very "alternative diet" friendly. I was vegan for 15 years and ate a lot of mirin and miso. SF should have everything you'd both want, although maybe not in the conventional grocery stores. I shopped Puget Consumer Coop, which is a chain grocery store carrying a wide variety of alternative foods. I'm not sure if it goes down as south as SF, but if not, I'm sure you'll find other similar shops.

As for weather, it can get a bit windy and cold. My husband travels to SF quarterly on business, and on his last visit (July) it was quite warm. However, for his next visit in October he's planning on bringing plenty of warm clothing.

I'm not sure about the ID situation, although I'd guess they'll want some assurance that he has a local residence.