In my experience (at grass roots level) I'd say about 90% of the time, the team taking a throw-in inside their opponents half loses possession within a couple of seconds which is of course exactly why players do as you've described above.I think there is a clear benefit to the player though, that's why they've decided to take it from there. They're throwing it straight to their keeper who has very little opposition, as opposed to the halfway line where players are marked up
I've learned that there is no real answer to this one except to do as others have suggested and choose carefully your hill to die on!!
If it happens in my game and there are vociferous protests from the opposing team/benches then I'll likely act on it. If nobody bats an eyelid then I'm just going with what that games expects and playing on.

