The birds do love them, they visit regularly even before the seeds form. Maybe they are staking claims. Maybe, since the aphids also
luv the sunflowers, they find snacks

.
I'm guilty of leaving too many sunflowers in the front yard, DL. The flower beds are an outrageous mix and throwing in some sunflowers is a bit much . . . Leaving them in the roses is probably criminal in some neighborhoods

. Still, it is nice to have the birds and some that don't seem to be here at home otherwise, show up on the sunflowers.
In the garden, I blame the sunflowers for my tomato plants never having hornworms over the last several years. Sunflowers may not be the best of close neighbors but, at a short distance, they bring in so many birds that I think they keep the hornworms out! Even seed-eaters, feed their babies insects primarily - not so with Marshall's pigeons, however. The chickadees are the ones I think may be the most responsible. All, add to my usual garden companions - the song sparrows and California quail.
You know, I had a friend who fenced an area for her chickens a little late in the year. Sunflowers had already sprouted and grown about 2 feet. The chickens killed everything else green in that pen but the sunflowers grew all summer and provided shade. I'm sure they would have eaten them if they were shorter but the plants soon outgrew the threat. I've even wondered about setting out potted sunflowers in the chicken yard.
By the way DL, there are smaller varieties like the Autumn Beauty mix that will make seeds but not quite overwhelm. Black oil seed sunflowers are also fairly short and quite pretty.
Steve