If you don't say that you are over 18 it boots you off the website. I've had it happen when looking at camping gear and at fishing equipment.Just the usual CYA to keep the legal department happy. I assume it was just an “are you over 18?” pop up, and not something actually asking for certification?
There was a very brief window of time, ca.2005, when I was buying a lot of my ammo (by the pallet, they could fork lift it straight into my pickup truck) at Cabella’s. I also bought one of my gun safes there, when their supplier had a big tent sale in their parking lot. But they’re almost always way more expensive than other options, on almost all things. I guess those fancy stores aren’t cheap to build!
It should say something, when local mom and pop gun stores can sell ammo by the flat (250 shells) for less than the big corporation buying and selling in bulk (5000+ shell
Edit: they must have changed it. I just went to both sites mentioned above and it allowed me to stay there. I was even able to look at 10/22 rifles... Not that I need yet another .22 in the house.