I know a course like this. Short holes and lots of large groups of teens. You can tell its more of an excuse to hang out and smole and make fun of each other than to actually learn. There are some teens who are interested in getting better at disc golf, but the ones who steal are not those guys.
Its actually the other nearby course that is more likely to have that kind of teens. But like Roadtripstuff said, they do go to this course and its not hard to spot them. But I think this would be true of almost any course that isn't out in the boonies.