"If he actually had been down and out...powerless in the face of society, in other words...it would have been just one more unpleasant incident in a life that already could promise little but a succession of unpleasant incidents."

That is making an assumption. If you have a bias that all authority figures are out to make life miserable then the outcome will never be acceptable. IF you choose to ignore all the times police and othes help the homeless and poor, then life will be full of unpleasant incidents.

You can choose between whether the glass is half empty or half full, or you can decide the water is also tepid and the glass is dirty before being served.