One thing that you also don't take into mind here is that 'zone' in this game (at least right now) means 'the entirety of Eorzea save instances'.
I'd actually love to see you, RahJah, chased all the way from Mor Dhona to Ul'Dah by a L80 hog.

I will also add that having stuff chase you forever and ever until you zone is still lame in my opinion regardless. Not only istwildly displaces mobs, completely undoing the concept of 'mob placement', it also allows training, MPKing and other similar goodies. That and it makes no sense for a wild beast to chase you across the whole wide world just because you stepped on it's territorry, it'll chase you away but that's it.

And it is also sincerely bothersome and doesn't even add anything to the dangers of exploration. Specially if they're full of range and faster than you, all it means is that you're essentially blocked from exploring anywhere where monsters you can't slay by the buckets are.