Atherton has nice little yellow signs that say 'No Through Traffic'. Why? They don't want the poor people from Redwood City coming through. In fact, one Atherton gentleman went to a RWC City Council meeting complaining about it and asking RWC to put up signs on their side too. The folks at RWC apparently told him to go stuff himself, that those little yellow signs were potentially illegal and if Atherton kept pressing, they would disallow traffic from Atherton through RWC. This was about two years ago.
The rich are different from you and me - they take because they can and because they can then get away with it.
[This is not to say that all rich are evil, nor all poor virtuous. Just that as money accumulates, so does power, and this when left unchecked by self-imposed moral constraints leads down this path.]