So are you saying that online e-tailers that sell things like triggers, magazines, rails, stocks and other accessories but do not actually sell firearms have an FFL shipping account or are shipping against UPS policies?The only firearm related items that you are allowed to ship via UPS now without an FFL contractual shipping agreement are optics and scopes, there's a specific exception for those in their policies. Even something as innocent as a bare stock, picatinny rail, or even a plastic AR grip are considered firearms parts and are now required to be shipped from an account with an FFL agreement.
I know I order quite a bit online from vendors that sell such items that would have no reason to have an ffl license as they do not sell firearms at all.