B) "spend a buck fifty and at a convenience station (they will often let paying customers use air for free) - and set the pressure to desired"
One of the few things California does right. Free air at filling stations. They can't make you pay for it.
You're paying for it. Look at that little price sign out by the road. Even if they are .01 higher on petro that's covering the compressor, hose and maintenance on that system.
