Most bloggers invite you to share their content far and wide on any one of many aggregation sites. But some people get really upset if you post that article on your own aggregation blog (even with full credit and back links).
I am always amazed when I get that proverbial chest thumping quasi-barrister “cease and desist” letter, followed by remedial citation of copyright law, and always ending with some pathetic accusation of irreparable damages and criminal violation. They get upset if you change the content and they get upset if you don’t. The worst is when it comes from a self-proclaimed social media guru who touts all ‘dat social media Kool Aid in their consultancy propaganda.