In my limited experience with so-called "spinners," writers would easily prefer to creating their own content as opposed to regurgitating phrases from a source article. This is usually more inexpensive and a better liked job for the writer. It's a little counterintuitive, but letting someone research a topic and develop content on their own (even when given SEO metrics) takes a good writer far less time so it ends up being cheaper & better.
Sometime you can have your cake and eat it too, although this doesn't solve a common problem when sourcing work . If the writer is uninterested or unfamiliar with the topic, the quality will invariably suffer.
* edited for grammar