Which means they can never update Flash or other installed software.
Yes, you would have to do that for them ( which in the long run would probably save you a lot of headaches ). As far as Flash goes, if they use Chrome, Flash is automatically updated ( as well a Chrome ) and you don’t need admin rights to do it.
Also in the case of Flash, it is good not to let them update it. Many viruses are installed by a pop-up that says that Flash needs to be updated ( it looks exactly like the one Adobe uses, but of course isn’t ) or by attempting to view a video on Youtube and having it say that your Flash needs to be updated in order to view it, and click here to update it - installing a virus instead.