This just happened to me a week ago. My buddy and I skipped a couple holes at a course and noticed I left a disc on the previous hole. I remember exactly where the disc stopped, because it hit a tree 100' out and dropped, and it was gone! I ran to the next hole and asked these 2 young guys, they said "No, but 2 guys just walked into the woods." So I responded "Yea...that was us, you were behind us and we jumped ahead." LOL!
In the end, I didn't want to start crap and ask to check their bags...but it was obvious what happened. If stealing my junky dx eagle makes you feel better, so be it.