...Photoshoots don't have models posing full frontal for the photographer's masturbation collection, but they A LOT MORE OBVIOUSLY have models posing for photos that are eventually given to them for their own purposes. Just because they are not made public doesn't mean the model isn't given them; models receive every image take of them. And not all people posing nude do it sexually.
Its pretty common that the models want pics of themselves in their prime so to speak. A lot do tasteful frontal nude shots, unless its Miley Cyrus, and depending on the photographers rep, for the models private portfolio before things go south or they have kids or are pregnant. In the past copies and negatives were handed over with some control, bit different with digital photography now for a model to be sure that they have the only copies. A good number of outtakes the get released, if the photographer is reputable, and pics are swiped by assistants, graphic designers and the like that get originals to airbrush out bits and keep a sample. Some photographers dont care and will cash in eventually, 'lose' master copies. When some models do get on a bit, to add some more length to their career, they release their younger held back raunchier photos and keep relevant for longer by getting in the spotlight again. Happens when they put on excessive weight too a they try to get trim again to bridge the time gap. Tends to be more reality tv celebs that do this than a Venus Williams but fair play to her, pretty tasteful, hot, and a reminder to herself even of her peak sporting condition so could be ok with it. I know any of this as my missus works in fashion publishing and hear some of the crazy goings on. Yeah strangely and maybe sadly i know my Vogues from my Cosmopolitans. Hope I dont get hammered for this post if it bumps the thread.