It's a quote from the same piece of classic literature that the GP is quoting from.
https://www.youtube.com/watch?v=fLIcFP0J5TY
JULES
– Okay now, tell me about the hash
bars?
VINCENT
What so you want to know?
JULES
Well, hash is legal there, right?
VINCENT
Yeah, it's legal, but is ain't a
hundred percent legal. I mean you
can't walk into a restaurant, roll a
joint, and start puffin' away. You're
only supposed to smoke in your home
or certain designated places.
JULES
Those are hash bars?
VINCENT
Yeah, it breaks down like this: it's
legal to buy it, it's legal to own
it and, if you're the proprietor of
a hash bar, it's legal to sell it.
It's legal to carry it, which doesn't
really matter 'cause – get a load of
this – if the cops stop you, it's
illegal for this to search you.
Searching you is a right that the
cops in Amsterdam don't have.
"Royale with cheese" is part of the same scene.