When I had to send my Thompson M1 back to Auto Ordnance, they did indeed pay for all the costs for shipping to and from, all the work was warranty, and my experience with them not too bad. (I don't think a single carbine comes out of the factory functioning, so I think they're used to it). What surprised me was no notice it got there, no updates, and no send and tracking notice. Weeks went by, and one day the FedEx van showed up when I was in the shop, handed me a case, no adult signature or anything, and drove off. I'm not upset about it, I just found the whole thing odd, a "you'll get it back when it gets there" handling of things.
I buy a lot of things at Sportsman's Guide, especially when there's free shipping, and there were times I felt guilty about taking advantage of the free shipping deals. I've noticed they aren't having hardly any more free shipping days like they used to, and wonder if the freight changes yet again are why.