When I used to live in an urban location, I used to regularly feed the sparrows and we ended up with at least 30 of them all at once, coming to the bird feeders. I would buy the mixed, husk free seed which was kinder to our lawn and they cleared the feeders pretty quick. We also had a few squirrels coming to the feeders, they are lovely but right little blighters who would chew through the feeders to get to the seed. We also had a sparrow hawk in regular residence as well, a beautiful animal, although the reason for it being there was not so nice, but that is nature I guess.
Now we live in a semi rural location, I have not seen a single sparrow, but loads of blue and coal tits and finches who love eating sunflower hearts! It costs me a packet, but it is worth it!
We also have a badger that comes under the feeders at night to take advantage of any dropped seed which is nice to see!