Blogs that use other people's content

[Mateusz]

Originally Posted by grandmascrotum

Where do we stand when it comes to this practise? Do we want to stop the unauthorised use of pics like this or do we tolerate it because it brings traffic?

Most content licenses don't allow to resell content and IMO 'lending' content for traffic is barter trade which may be judged as reselling.
Anyway... if you may resell pics you own I think your question should be considered AFTER blog owner ask you for permission