Wait, it's one thing for someone to take photos of their friends and post to Facebook or Instagram. If anyone were to use them for profit however, do the people

Wait, it's one thing for someone to take photos of their friends and post to Facebook or Instagram. If anyone were to use them for profit however, do the people showing in the photos have no rights? I'd think that it's not actually as simple as you put it, but that the people appearing on the shot have no reasons normally to go after their rights, but in reality they usually didn't give written consent for being shot (I don't think posing for a photo qualifies as legal consent for the photo then to be used however the photographer wants, much less by third parties.)