TBH I agree, they shouldn't allow SBing in DF groups. Too often I see people drop lower than the dungeons minimum iLvl while spiritbonding. This people are wasting the entire parties times for personal greed, and that shouldn't be encouraged. It's selfish and inconsiderate, and not even optimal (SBing outside is way more productive).

If they want to SB in PF that is fine by me, as long as everyone agrees on it. But on DF? That's just outright rude.