This is the most likely answer. Just as it was the large grocery chains that have funded all the plastic/paper bag bans.
The gun lobby has a long history of trying to ban low cost market entrants.
Is this not like a schizo conspiracy theory? Like why would the grocery chains fund the bag bans? So they can save a tiny amount of money on paying for bags?
But having to bring your own bags limits how much you can buy. If someone has a plan to just use their own bags, they will likely forgo purchases at a higher rate than if the bag is not in the equation for them.
It's not obvious to me that the buying limit effect sales decrease would not outweigh the savings on physical bag purchases. Maybe I'm not following?
This is a well documented Everytown campaign, you can't blame this one on firearms manufacturers.