I sent off an email:
I wanted to make you aware of a recent shopping experience I had.
My family and I were intending to visit your store and shop for our monthly grocery list, however upon our arrival we were greeted with a sign at the door stating 'NO GUNS ALLOWED'.
This sign presents a serious concern for my personal safety and that of my family.
Given that the only people who will heed these signs are law abiding citizens and given that predators statistically target areas where victims are less likely to be armed - these signs do nothing to ensure the safety of your patrons. In fact, there is good chance that you are putting your patrons at an increased risk of harm just by posting these signs.
Given these facts and the fact that many of your competitors in Nevada respect the second amendment of the US constitution by following State Law and allowing their customers to protect themselves in a way that the Federal Government sees appropriate rather than taking measures into their own hands to disarm law abiding citizens, I must regretfully inform you that neither myself nor my family will be shopping in your stores until these signs are removed.
Further, I will do my best to ensure that my friends, coworkers and anyone I care about is aware of the danger they are being put in by shopping in your stores.
In the future my business will be given to stores like Winco, Walmart and Sam's Club - who maintain my right to defend myself and my family, whose policies don't circumvent State Law and who don't advertise a 'gun free zone' for predators.
Hopefully it helps.