Most stores have that policy (securing firearms on entry) for firearms being returned or repaired because they will be handled in the store, and the store is guaranteeing that they will be handled responsibly. Very ofter managers mistake that policy as covering all firearms in the store, including those being carried lawfully in a holster with no intention to handle them unless needed for lawful self-defense. We had such a misunderstanding with a store in Montgomery, Alabama until corporate clarified that the only firearms that need to be secured are those being returned or repaired. When the policy was clarified, we had an event at the store and spent some coin there.
That being said, I don't know Cabela's policy. I suspect it is essentially as stated above and needs to be communicated clearly to local managers. Thank you for working to get corporate to clarify it.