Yes, even when paying for art this can and does happen. I think some time ago there was a case where someone put a photo from the phillipines on Twitter, an age

Yes, even when paying for art this can and does happen. I think some time ago there was a case where someone put a photo from the phillipines on Twitter, an agency downloaded it, and sold it on to customers, several of which had to pay millions in restitution to the original - and probably somewhat happy - photographer. The more I know about copyright law the less I feel like creating anything at all. Here in Germany I can barely publish any photo with a child anywhere in it, and it gets only moderately easier with adults. Everything requires consent forms.