Unfortunately, people tend to flood every single gallery, group etc...that has anything even remotely connected to the vid. with the same videos. It's be nice if folks would post it to their own gallery or groups.
It would save lots of server space and save everyone tons of time weeding through the same few hundred videos in every single group or gallery they are a member of.
As the owner of the vid, I'd think of you deleted it, it's go away. But folks can download it, retitle it add tags related or not and just reupload it.
Once you upload it...it never truly goes away.