They don't compare. One group has their homes "impacted" (they are inconvenienced by the sight of poverty), the other group doesn't have a freaking home.
Or, you know, wake up to find shit on their driveways, smashed windows on their cars, needles thrown on the street, etc.
Rationally you can think "that's just the mental illness or addiction causing someone to behave that way". But over time, even if you rationalize the behavior it wears down on your empathy.