Pigeons don't fly away in winter. Of course, they are cold in severe frosts. They fluff their plumage for warmth and look for warmer places where heating mains pass or on buildings.
People feed birds living in cities or nearby forests. They hang feeders on trees. Sometimes they are beautiful and neat, made of wood, but often they use plastic bottles. There they pour crumbs, cereals, seeds for birds. And they most often just throw food on the ground for pigeons. But these pigeons did not wait and climbed into the feeder, intended for smaller birds.