Because they are covered all over with stars! Don’t fall for that.
They really look like polka-dots. These birds of The Birds fame are probably one of the least popular birds in America aside from pigeons, partly because they are very social birds and tend to gather in huge flocks, landing all together in one place and squabbling and eating everything and leaving their droppings.
Up close they have strangely intense faces without the wide-set clear round eyes we are accustomed to on most songbirds, just beady dots in the midst of all those other polka dots, and their whole face seems to be pulled to a point by someone tugging on their long, thin beak.
But their feathers are beautiful, colorful with multiple patterns of dots, tail and wing feathers edged in white.
Here a European Starling plots an entry to the feeder.