Thanks for your questions “What is the most romantic restaurant in or near Sacramento that does not serve alcohol and at the very least is non-smoking whose main venue is not a bar/tavern/pub/night club?”
I think this questions romantic restaurant is very important for all like yours. Here I’m trying to give your answers in brief.

If I want to answer this a little more clearly I’d have to know what your objection to being near alcohol is. There are some places who cater to recovering alcoholics by removing wine lists from the table and approaching seating from angles that do not lead past displays of wine, but in general fine dining (and unless you consider Olive Garden to be ‘romantic‘, fine dining is where romance happens) does use alcohol in preparations (safe for most sober drunks since it avoids both the substance and taste trigger) and offers wine and spirits lists (not safe, but can be circumvented).

Smoking doesn’t happen inside any place in California so that one shouldn’t be an issue.
If you have a moral objection to other people consuming alcohol in your presence or too patronizing places that serve it, fine dining is mostly out unless you find a Halal place, but they’re traditionally more fast/casual focused.

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