I guess I am missing the point of many here. I am in favor of armed police being in a store going about their business. Even if he was officially off duty. What am I missing? Off duty cops will go into action if they find themselves at a crime scene while off duty.
Cops are used to being treated differently and it's often a harmless, in fact, good thing they are.
When it comes to the Bill of Rights, though, why are their rights any different than those of anyone else?
The leeway and authority their job as a police officer grants them shouldn't include retaining their inalienable rights when off duty while everyone else is denied those rights.
Tell the off duty Police Chief or Mayor in some large city that they and/or the officer(s) escorting them have to leave their guns in the limo and see how that goes over. There's no reason for the nobility and their servants be sure that their rights will never be denied while the "little people" are routinely denied the rights our Constitution says are inalienable.
It's artificial differences like off duty police being able to ignore what everyone except the political elites have to deal with that subverts police forces into political weapons, not free coffee and donuts or a free dinner now and again.
The officer should have never been told to leave his gun outside not because he's an off duty police officer but because it's a Constitutional right. If there are places that deny regular folks their rights then they should deny off duty police those rights as well.
An off duty officer feeling naked when something starts is just a case of what's good for the goose being good for the gander. They can call 911 like everyone else is expected to when they're denied their right to self defense.