[lxgr]

You're highlighting an important edge case here: The TZ database only splits regions reactively, not proactively.

But an actual lat/long pair is often neither available, nor desirable to be stored for various reasons.

Now that you mention it, I think I've seen some web applications that had a list of cities much longer than what's present in the TZ database for calendar scheduling purposes, probably to accomodate for just that future edge case.

[BeFlatXIII]

I appreciate those longer lists, though they do have some bizarre omissions.