Earlier quoted context omitted.
You're right, they shouldn't of fed the homeless.
Give me a man a fish vs teach a man to fish. The system in the US is broken, the Thanksgiving dinner for the homeless is only a flimsy bandaid, and the real reason it's pernicious is because now the volunteer can sit back in the warm glow of approval on Facebook/Instagram and think "There! Now I've done my part".
That said, I do think it's silly and pointless to "help" on Thanksgiving. These places are overrun with volunteers on Thanksgiving but not at other times of the year.