Swag is free stuff. I understand that companies like to call their paid for promotional items "Swag," but if you paid for it, I would call it an "affinity purchase." Shirts, hoodies, and jackets emblazoned with giant corporate logos (Nike, Underarmour, and Tapout come to mind) also fall into this category.
I like hats and stickers too, and I put that (free) little Geissele zipper pull on my jacket. But, I am very reticent to be a billboard for a company- even more so if I have to pay for the honor. Free hat? Sure, I'll wear it. $20 cranium-mounted billboard? I'm much less likely to partake. Free stickers? Sure, I'll put them on the gun safe or gun case. $1 sticker? Nope, you can do your own advertising.
I'd bet they did some algebra and figured out that the store wasn't selling as much as they thought it would...