Age of Wonders
In the far future, advanced flexibility has been finally embraced by many creative people as one of the ideals of human beauty, along with strong muscles and visual attractiveness.
If someone shows a painful grimace when seeing a contortionist, he pretty much exposes himself as an uneducated retard. It is widely recognized that stretching to become a contortionist isn't any more painful than working out to grow muscles or starving to become a fashion model.
Bodybending gradually becomes as popular as bodybuilding and fashion, and it is the subject of many paintings and sculptures. Flexible poses can easily be found in art museums and sometimes they even take a big percentage of all works.
There are special gyms where the future bodybenders have the access to all the many training devices designed specifically to improve backbends, twists, oversplits and so on. The are professional trainers who would help a child to take a seat upon his own shoulders for the first time in life. Children actively practice some exercises from wushu and kung fu to gain full control over their own flexibility.
When they grow up, one of the many applications of their flexibility would be to become a model for photographers, sculptors and painters. Most of them choose photography because it's interesting, not too difficult and a fairly quick process, and there's a great chance to get in some glossy mag and even become a celebrity. Crafted art is a much more advanced business since the model needs to hold a specific pose for a long period of time during the process of painting or sculpting, but it usually pays a lot more than photography and the resulting artworks as a rule are extremely pricy.