The prevalence of this kind of "live/work" space in SOMA is an artifact of the "building up" that happened the last time there was a technology bubble. We can see how well that worked out: a lot of people were evicted from older construction, only to have it replaced with more expensive new construction that is mostly being used for business purposes, because no actual human beings can afford it.
Most live/work building's rules will require that you maintain a business license. Although most live/works are used primarily if not exclusively for housing the city does not seem to care as long as they get their license fees.
Did you just make up you "facts" to support you ideology? Give the reverse a try someday. ;)
[1] http://www.sfgate.com/bayarea/article/How-S-F-s-live-work-de...
[2] http://www.sfgate.com/bayarea/article/Fees-considered-for-S-...
I don't know if "most" live/work units require a "business license", but I know that they weren't intended to be office buildings -- which is what you seem to be asserting. They were the "solution" to artists being pushed out of the city during the last major boom. And it backfired.
