Sent them the following email.
To whom it may concern;
My name is ***, and I frequent Harvey's when I visit my parents up in Gladwin. I have recently been informed of your 'no gun' policy posted on your door. Though I understand that you try and create a family atmosphere for all at Harvey's, I encourage you to re-think this policy. As a lawful firearms owner and a daily carrier of a handgun with a Concealed Pistol License, I know for 100% positive that a simple sign will not deter crime from your establishment, and it would be silly to believe that it would. I encourage you to watch this short YouTube video on 'Gun Free Zones' when you finish reading this:
Though I do like your establishment and do wish to return, I simply cannot bring myself to frequent your location with a no firearms sign posted. Myself, as well as every other person with a Michigan Concealed Pistol License are all law abiding citizens, and you have absolutely nothing to worry about from the 'good guys'.
Michigan Open Carry Inc.