Does anyone actually use article sites (like ezinearticles.com) as a source of content?

Yes, I use Ezinearticle often. Its a great source. Just look for the author who have an excellent author status. Of course they are allowed to keep there urls and names if your are going to publish there material. You can get something for nothing. Its the best way to share content and build site popularity. Those outpointing urls are good for your site anyway.