It's part of their denial, the constant pointing at the "them, those people," the eternal, "other."
By demonizing certain people as the major recipients of public assistance, psychologically they somehow feel they're exorcising themselves from what they are and do.
And I mean more directly, not just as a demographic. Like those who constantly punctuate every sentence with "us" and "our" - giving away if they're actually foreign and not part of any such "we," those who complain the most give away that they are what they claim to loath.
From 1992 - 2013, I lived in an apartment in a slum. The people that I knew that were the most judgmental, pointing fingers, gossiping about others as welfare, etc, recipients.... they not only turned out to be receiving benefits as well, but often doing so as scammers, using every trick they could to milk the system beyond that for which they qualified for. Each. and. every. single. time.
Instead of being sympathetic and appreciative, they sought to bring down others in the same boat. The punchline was, the second they turned around, everybody else was spilling the goods on them. This was around Arthur Avenue in the Bronx, which is both an urban neighborhood, but also has a small town feel, with everybody knowing each other's business. So attempts at deception is just a silly exercise in inane futility.