Because homeless people is just a big group of nameless, faceless people. It is not possible to care or not care about them as a group.

I met a homeless guy with kids once. He didn't want to admit to them he was homeless so his solution was just to never talk to them again. Great solution. He also said he didn't want to go home because he didn't want to have to admit to his wife he was still on drugs. Oh, and he didn't want to go off the drugs because then he would be bored. Yes, here is a really responsible type guy that I should care heaps about!

I stay awake nights worried about him because he might run out of drugs! I figured that I if I did without a bit of necessities I could give that guy just enough money each week to make sure he can stay high while I go out and work.

I heard a homeless guy once quoted on a report that he did drugs while homeless because he was bored. He said there was so much time in the day that the drugs helped pass the time. He could have instead spent his time cleaning up the garbage on the sidewalks or done odd jobs, but no, he was bored so he had to drug himself. It was great stuff.

At least he was honest I guess.