From the "Rights" section at http://instagram.com...al/terms/updated/
Some or all of the Service may be supported by advertising revenue. To help us deliver interesting paid or sponsored content or promotions, you agree that a business or other entity may pay us to display your username, likeness, photos (along with any associated metadata), and/or actions you take, in connection with paid or sponsored content or promotions, without any compensation to you. If you are under the age of eighteen (18), or under any other applicable age of majority, you represent that at least one of your parents or legal guardians has also agreed to this provision (and the use of your name, likeness, username, and/or photos (along with any associated metadata)) on your behalf.
Oh wait, they're not talking about you :-/