Jax isn't a romantic city. Who cares? Most cities aren't. I can totally see SF at #1, even with its more expensive dinners for two. It's a very romantic city. And # florists is a pretty good barometer imo. The study put Miami at #1 and Atlanta at #5 for this measure. I'm not sure how they arrive at their numbers, but I've never been in a city with so much accessibility to flowers in my life as San Francisco (I'm very familiar with both Miami and Atlanta and they don't seem special in this regard to me). Aside from florists, every block in the financial district has a flower stand. There is also the only wholesale flower mart in the country right in the city and a major developer is spending $86M to keep the flower mart on-site so it can build 3 office towers above it (community outrage at the thought of losing the flower mart forced the developer's hand).
Anyway, I digress. I live in the #1 Valentine's city and went to bed early on Sat night. So it's not #1 for everyone

If I lived in Jax, I'd probably already be married by now. Haha