Actually, yeah, that's a point: Summoning and containing in a circle to have a conversation is one thing. Harry made a point that when he summoned Toot, he *did not* bind him, when Morgan came out with the big pointy bit in his hand. Chauncy's similar, even: he's certainly not bound into service, he's just showing up to have a conversation. *Kalshazzak* on the other hand was a bound demon, compelled into service.