Their focus wasn't on the product, it was on living/working in SF. They could have saved a year's worth of AWS payments alone by trimming the fat that comes with wanting to be in a "hip" location.
I know what you mean, SF is too expensive. But it's basically impossible to relocate a team of 7 who already have various different ties to a given area.
For product development, remote working is one solution. I work remote with my team all the time. Sometimes you need to see each other face to face, then meet up somewhere where it's affordable. Could make for a good team field trip even!
Does office space for 7 employees in SF really cost ~10K/month? I know in midtown Manhattan a previous startup I was at had over 5K sq ft for that price.