In winter they do change their eating habits to take advantage of the warmer daylight hours when food is scarce. I don't know if you live in a cold climate but here in the N.E. it's really not that uncommon to see them in the daytime in winter.
[ What is life? It is the flash of a firefly in the night. It is the breath of a buffalo in winter time. It is the little shadow which runs across the grass and loses itself in the sunset. - Crowfoot, 1890, on his deathbed. ]