Well, this is a rather interesting topic.
I think, what it boils down to, is that somebody said it's this way, people do it this way, it will be this way. If you want to push a change, it will either not catch on or fracture the already smallish community. I'm fairly certain everyone could find something that they could improve in toki pona, but that would mean trying to rally people behind it and whatnot. I really do believe you that it doesn't make sense, and it probably is because of a fleeting quirky thought. But, it's here now and it can't be pushed away.
To me, the far greater issue where this comes up is numbers. It's in the same vein, except everyone comes up with their own way to deal with it or something.
But, as I've learned, it's just a hobby really. Nobody is taking it too seriously, because, well, what's the point?
However, I think, and I think other people might be with me too, if there was anybody to really just go at it and make consistent toki pona texts, these things could be flattened out. As in the previous mentioned examples for case in other languages, where one form or another just went out of style due (to what I assume to be) to popular taste.