If monthly rent in SF is between $4.63 and $5.35/sqft[1] then the value of an additional ~130sqft[2] room would be at least $600/month. An unfinished garage space is probably a little less so let's say the value of a garage is $500/month. As long as you get four or fewer tickets per month then it's still cost-effective to continue to park your private vehicle in the public right-of-way and continue to use your garage for an office, gym, storage, other car, etc.
Something similar happened in NYC. Renting a garage became more expensive than just paying a couple street sweeping tickets a week so many people started keeping their car on the street and treating the tickets as a parking fee.
[1] https://www.renthop.com/average-rent-in/san-francisco-ca [2] https://www.dimensions.com/element/parking-spaces