I read to the 7th page and got tired.

The reason why the auto-kick AFK function does not exist is because, they did not have it in their other MMO which has been around for almost 11 years now, as well as ffxiv 1.0 so players could run an in-game shop. I am going to make an assumption that most of the AFKers are previous FFXI / FFXIV players. As well as that in 1-2 months from now, the population will have decreased a significant amount meaning there is no real reason to implement an auto-kick in the first place.

This is a week 1 launch of an MMO, there will be issues, be patient, it is a virtue after all.