Where they got this idea, I'll never know, but I do know they did not get it from Scripture.
"The early church never preached the good news without tending to people’s physical and material needs."
Never? It's not like the apostles traipsed into cities and started soup kitchens and housing projects before they started preaching.
Time to get real, people. The church's one mission is proclaiming the gospel. Once people were converted, they took care of their own. That is what the Bible shows.