When I first saw this bike parking contraption outside Walnut Creek City Hall I assumed it was for city employees, but based on this map that shows BikeLink public secure parking locations it looks like anyone can have access to it for around 3-5 cents per hour. I guess for those with expensive bikes this might be worthwhile. From the BikeLink website:
BikeLink is a secure on-demand parking system for small vehicles designed to make it easier to use transit and other mobility alternatives. It enables convenient and secure temporary storage of your bicycle, electric bicycle, or scooter. It also enables automated vehicle rental.
The map also notes that this is coming to Lafayette and Orinda BART stations soon.