Snapchat just reserved the rights to store and use all selfies taken with the device
The beauty of Snapchat is that the photos only last for a few seconds, unless your friend decides to screenshot them.
Even then, you get a notification, so can know exactly which photos of you are owned by someone else.
However, now, the app has changed its terms and conditions so it owns every single photo taken using the app.
Not only this, but if you use it, you're consenting to the app doing whatever it likes with your photographs.