same with png..
I´m working on a rpg-maker in 3d. I can´t say to the users "Just make a TGA und create a alpha channel..and..and.." many users don´t know how to use that..
If you have an idea, how to read ong, and use it´s auto-transparency, it would be better to use for inexperienced to use the rpg-maker.
i don´t think that´s stupid.. I think that´s user-friendly.