Left-wing interventionists may be sincerely motivated by the desire to help the poor. But, as I pointed out in Economics for Real People, to strengthen the state in the interest of helping the poor is a fool's game. "The powerful" aren't called that for nothin' -- they're going to capture whatever mechanisms of power are put in place and use it for their own ends.
Witness the Kelo decision, where the homes of poorer residents were seized for private development. Wikipedia notes that when the case came before the Supreme Court, "The NAACP, AARP and the late Martin Luther King's Southern Christian Leadership Conference... signed an amicus brief arguing that eminent domain has often been used against politically weak communities with high concentrations of minorities and elderly."
Too late, my friends! If you had stood up for the property right of a restaraunt owner or landlord to reject customers for any reason whatsoever, maybe you would have had a chance in Kelo.