Did you intend to ask, "...rationalize NOT helping the poor....?"
All of the conservative Christians I personally know are Republicans who spout the party line and loudly complain that taxpayers foot the bill for any government-sponsored social welfare program, such as food stamps and Medicaid--anything that helps the poor, homeless, unemployed, veterans, needy children, elderly, etc., all of whom are presumed to be just lazy layabouts who refuse to pull themselves up out of poverty by their bootstraps. These people also vociferously protest the Affordable Care Act (derisively referred to as 'Obamacare') and want to have it repealed with the help of the Tea Party bunch.
(Remember, please, that I live in the poorest state in the U.S., Mississippi, where the R. governor fights anything and everything that might help the state's economy or any of its citizens other than his affluent white male Republican cohorts and their Stepford wives and children. I know I'm cynical, but it's how I manage to live here and maintain my sanity.)
These are the same people who frequently proclaim their piety and quote biblical scripture on social networks, in casual conversations and on bumper stickers. I fail to understand how they can reconcile their vaunted religious beliefs with a determination to NOT help the poor, especially when the teachings of Jesus focused heavily on caring for those who need help and were demonstrated by example.
I know I didn't really answer your question. I've been wondering the same thing myself for years. The word 'hypocrisy' springs to mind.