The law of trespass has long hinged on legal inferences about what is and isn’t an implied invitation. A girl scout may ring your doorbell to sell cookies, because your doorbell and the paved walkway to your front door implicitly invite that behavior. But the same scout might very well be trespassing if she walked around to the back of your house.
The law of implied invitations has evolved over time. For example, over the course of the 19th century, most states reversed the default rule as to whether domesticated cattle were permitted to graze on another owner’s land, thereafter placing the burden on the visiting rancher to obtain that owner’s express consent. More recently, some cities have flipped the default and now prohibit peddlers from solicitation on private property without the owner’s consent.
The evolution of implied invitations to enter private property has also applied to gun use. Traditionally, armed strangers were permitted to enter onto unimproved rural land to hunt — unless the owner posted “No Trespassing” signs along the land’s perimeter. But now half the states have flipped the presumption so that it is trespassing to hunt on private property without the owner’s consent.
The law of implied invitations evolves because social norms change over time. Customers generally understand that, by default, they are not allowed to bring their (non-service) animals into a hotel room or a restaurant. They must look for “pet-friendly” or “pets allowed” establishments. But customs can change, and it is reasonable for the law to reflect that change. …
In light of this evidence, New York and other states should respond to the court’s injunction by enacting a new requirement that businesses holding themselves open to the public affirmatively state whether or not they want patrons entering their property to carry weapons.
An “affirmative choice” rule of this kind will make clear that it is the property owner who is making the decision, not the government — and so there is no government restriction on the right to bear arms, or even a finger on the scale for or against concealed carry. A neutral law of this kind cannot violate the Second Amendment.
— Ian Ayres and Fredrick Vars in Patrons Packing Heat: Businesses Should Be Required to Tell Customers Whether Guns Are Allowed