Why is it legal for stores to sell marijuana paraphernalia? Why are some but not others shut down?

Bob B asked:


I have recently seen reports of several shops (everything from a headshop to a gas station) being shut down and fined for selling pipes, bongs ect… The law states they are legal so why are they raided sometimes? How can they be legal? They are obviously used to consume marijuana. Now lets not turn this into a discussion on if weed should be Buy cheap Cialis legal or not but how can it be ok to sell sometimes but not other times? Technically how can a piece of glass be illegal to sell?