- Chosen by Voters Because a lot of them have nude or partially nude scenes or other sexual content. There are child labor laws that don't allow such activity with children under the age of 18, so the "teens" need to be actually older people. I know that 18 and 19 is still teen and legal, but there are some states that consider someone still a minor until 21. So having actors be over 21 covers the movie makers legally. 2 weeks ago 43% 3 Votes 3 people rated this as good