How Can We Stand The Suffering?

Today, as I sat outside a local downtown yuppie food market, I witnessed employees of the market physically detain an elder gentleman who had shoplifted food.
I watched as the man sobbed loudly and begged them for forgiveness.
I watched the employees take his photo, look through his wallet for ID and stand menacingly over him as he cried.
After the manager came out and talked to the man, they let him go, and I approached the manager.
"I don't think your people have the right to put their hands on someone like that." I said.
"We can do what we need to do to run our store." He responded.
"It's the police's job to detain someone," I said "You don't have the right to put your hands on someone."
"What business is it of yours?" He asked.
"It's my business when I witness an assualt."
"Listen, buddy. You don't have to deal with people pulling knifes on you and threatening to kill you."
The old man had no knifes and was making no threats, but all criminals are the same to some people, even if they are hungry old men.
This is where I lost my composure and started demanding of the manager that he try putting his hands on me if he was so fucking tough.
He looked as if he was considering it, but I guess he'd had enough violence for one day, and decided to go back to his job of selling over-priced food.
I'd had a hard day already by that point. I was sitting in front of the store pondering how people could tolerate all the suffering that one sees downtown every day. I sat there pondering how people can walk by old women and young children, or anyone suffering on the street for that matter, and not see how serious a crisis we have in our country.
I cried with frustration all the way over to a friend's place, and cried for another hour as I described what I had seen and the thoughts that had been going through my head today.
A big part of me wants to get out of this city.
Another part of me wonders what would happen if everyone who cared had this response.
Is that the only response I can manage, to put it out of sight and out of mind like everyone else?
Having ended up on the street myself, I am even less able to do anything about this situation than I was before.
The frustration just keeps piling up.
I've gotten to the point that anyone who refuses to see that homelessness is a disaster in need of an immediate response is not worth my time.
And another day passes where I have even more disgust for this society.