Should brands be allowed to share people's Instagram photos for free?

I'm interested in writing an article about brands and publications sharing other people's photos on Instagram. I want to gain as many thoughts and experiences on the subject as possible - is it illegal? Do you find it's beneficial (as long as they tag and credit you)? Should the company sharing pay to use your work or is the "exposure" enough?I want to build up a full picture with thoughts from various sides of the argument, so please let me know your feelings! via /r/photography http://ift.tt/2tSC2eH