Should I try to keep the rasp?

Hint 1 of 6:

Of course!  Kleptomania is the first skill of all good adventurers.  But
you'll have to get Max to give it to YOU instead of back to the soda jerk.

Hint 2 of 6:

First, you'll need some privacy.

Hint 3 of 6:

The soda jerk might not want you to keep the rasp, so you'll need to go
behind his back.

Hint 4 of 6:

Or, rather, out his door.

Hint 5 of 6:

Now, if you can just get Max's attention.

Hint 6 of 6:

Max may be headstrong at times, but he knows a good idea when he hears it.