If the LEO is there on official business the owner of the store cannot prohibit the LEO from bring their guns. That would be interfering with the police.
Now off duty I guess they can prohibit them.
Still that is the most stupid 'gun free zone' of them all!
But folks, that won't happen in TEXAS (at least I hope we don't go the way of California or Illinois and do such stupid things.)
"The government has confiscated all of our rights and is selling them back to us in the form of permits."