Contrary to what many assume, laws are not always clear. Some are so unclear that not even formally retained legal counsel can give consistent advice to a retailer. And the regulatory agencies are seldom inclined to offer concrete opinions.
Faced with those sorts of uncertainties, it’s up to the retailer. Each individual retailer always has his/her own personal preferences about how much risk they are willing to incur, when selling to a particular customer in a particular state. Smaller retailers, with shallower pockets, are less able to defend against lawsuits or mount a legal challenge to regulatory decisions; they opt for lower risk.
And guns/ammunition are but a small part of the total equation. State governments grow more insistent with every passing year, about collecting sales tax on transactions that cross state lines. State revenue departments believe that citizens who buy stuff from out of state are greedily and immorally circumventing local tax laws.
Agreed. Thought that’s basically what I wrote, but I did segue a bit...