There are people that still want to use software after the trial period is over. So they think let me uninstall it, and reinstall it, and I will have a trial period reset. Wrong and not very smart. Even if you use an uninstaller like Revo in expert mode it won't delete that particular file or registry key.
The product will uninstall itself but puts something extra or does not delete something to just prevent that. So every, and I mean every software manufacturer just puts something in the registry or in some hidden file.
That's just what I was refering too, and having access to that information is just that and doesn't mean I would use such despicable method to try to use software again after the trial period.
Knowing that