I visited the Space Centre in Houston as few years ago with my family. We stayed in the Holiday Inn just across the road. In the morning, we asked the front desk if we could leave our car there for the day and walk the few hundred yards to the centre. They looked at us as if we were from another planet (well, we are from the UK, where walking is not seen as a sign of incipient madness!). Then asked "How will ou cross the road?" pointing at the 10 lane highway between us and our destination. In the end, we submitted, got into the car, joined the highway and immediately turned left off it to get to the other side...
That said, I do find Northern California to be the most pedestrian-friendly place in the US west of Boston.
A similar situation exists at New York's LaGuardia airport. I never did see anything that looked like a pedestrian walk headed toward any exit. Of course, that is not the area where one would find any destinations within a walking distance, I don't think. Detroit's Metro airport is even better, in that the reason is that there is nothing near at least one of the exits that a person would walk to if they could. Of course, I have not investigated the other, new, exit that is for going in the direction that I would never use. But it also does not seem to have anything approaching even a shoulder for a person to pull a disabled vehicle onto. Oh Well, this IS tthe Motor City.
Reminds me of the time my colleague and I tried to walk from our hotel in Orlando, FL to a nearby conference. No sidewalks after a few blocks, and a police cordon on the highway shoulder where a pedestrian had just been run down that very morning! Sobering. After a short hike through some woods, we came out at the conference facility, but on the wrong side of the security station. Needless to say, the guard was not amused.
For more "you can't get there from here" pedestrian hijinks, I recommend reading Bill Bryson's "A Walk in the Woods".
I've only lived in the area since 1995 but still long before terminal B. The area around SJC has always been hostile to non-motorized transportation. That is an unfortunate routine for airports the world over. The only exception that comes to mind is Medan, in Indonesia.
There is an old saying -- "Will will find a way". And so your will found a way out of the flowerbeds and dirt . Surprising to read that such a thing happens in US, where the roads are designed in such a prefect manner that you can blindly follow the signs to reach your destination.