( It'd be difficult to refuse food when Luffy is offering it, and no-one would ever judge Nami for taking bites out of the offered sandwich. That and it's multitasking the the nth degree, in Luffy's mind they'll need the energy from when they have to invariably run for it one they're out.

The whole concept of lockpicking is a fascinating thing, brown eyes watching each movement Nami makes with her tools. The fact someone could open a lock with a piece of metal is a big deal and something Luffy knows he could never replicate. Sure, he could break a lock, but this is something else and the pirate captain is loathe to interrupt it. Sneaking out is easy for him, but breaking said lock would bring the guards crashing down on them. And why would he want to get in the way of Nami and the challenge of picking a jail cell lock? )

I didn't see much, but there were some bags on their tables in the next room over. Looks like it could be our stuff.