They are pretty shady. But it might be good to have somebody, once the primaries are over, who can get together and say "Okay, these two are never going to concede to each other, let's throw it to one of them for the sake of the party."

Especially if the alternative is for the nomination to go to some third "dark horse" person who Barrack & Hilary can agree on but no one actually voted for.

Otoh, regular delegates could do this too. Just probably not ahead of the convention.