Ever start to walk into a store and see a sign saying it was a "weapons free zone" or the equivalent thereof?  I have.  And I have gone through the effort to get people to write/protest and get the sign taken down.  It's a lot of work.  Here's another way to perhaps change things.  It's a "business card" you leave with the merchant instead of leaving them your money:

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Only $10/100.  I just ordered some.  I wish I had them with me now.  I am going to the Seattle area tonight and would drop one off at Half-Priced Books in Bellevue.