When I was a steward at Withdean it was in my job descripton to get people to sit down. I assume you'd have been happy if I'd thrown dirty water over you if you stood up ?
Although the video makes it look like he was on the pavement outzide the station rather than on station property. Regardless it's still a shameful way to treat any human.
The answer is to treat them as a human being. I wonder how quickly you would be on the street if your shop went bust ? I despise how people treat the homeless - when I'm out if I have a few spare minutes I buy them some food and drink and have a chat. You'll be amazed how many of them ended up...