I get lucky runes, it is indeed useless, but seal treasure?
I actually spent some in there myself before learning of Tendo treasure, and I got myself Tobi (when he was good), but it's * later on, it gives low levels a chance of getting someone good early on though, new players. Even if it's only free pulls, it's not entirely useless. Plus it's free fragments and stuff later on, so may as well take it, right?