I think in both situations, further consideration is needed because of the nature of the existing relationships. Kim and Jimmy are throughout the show at the ve

I think in both situations, further consideration is needed because of the nature of the existing relationships. Kim and Jimmy are throughout the show at the very minimum, friends, a lot of their conversations happen as friends. You can't just claim "consultation" to privilege a conversation. The nominal fee is to distinguish this conversation from others they have. Same thing with Saul and Walter. Up until that point, they were speaking as hostage and kidnapper. So to distinguish the change in the relationship, he takes a nominal fee. Now they are a lawyer and his clients.