If he puts the cookies in his pocket, he's going to have a pocket full of crumbs by tomorrow. It doesn't matter if Will has a point or not: what matters is Will has gotten his hands on cookies, and has deemed them as Nico's shadow travel stash, so into his pockets they go.

Because he's not just offering Nico cookies. "If you were just offering me cookies, you wouldn't have brought up shadow travel. You'd be telling me I need to eat something."

Not talking about being safe. But he doesn't keeping prodding at the logic. The cookies are already in his pocket. "Are they going to charge you more money if I'm here?"