TexasCHLforum.com

Some firewall products have broad categories in what they block. Depending on the vendor, firearms categories might be in adult/mature content and they may just have the entire category blocked instead of selecting each individual item withing the category. For example, the firewall I manage at church has everything from alcohol, dating, gambling, adult content, lingerie and swimsuit, sports hunting and war, tobacco, and weapons all in the same Adult/mature category. I block the individual items that we don't want, not the broad category.

So it just may be laziness or their policy is not clearly defined on content they want to block. But they might be blocking it intentionally. Only way to find out is to get Sam's Club to respond to a request if they are intentionally blocking it.