Absolutely positively 100% legit, PayPal Digital Gifts is a huge seller with over 250K feedbacks, I've bought dozens of GC's from them (but never SWA's).

I find your second statement rather interesting as my experience has been the complete opposite of yours. I've been an eBay user since the late 90's which I call the Wild West days of eBay where scams were rampant. However, I've found that - at least from a buyer's perspective - eBay has become a MUCH safer place to buy in recent years. My impression is that in disputes eBay and/or PayPal (now totally separate companies since eBay spun off PayPal in late 2015) will almost always rule in favor of the buyer, sometimes even when the buyer doesn't really have a leg to stand on.

PS: if you fully understand the Kroger Plus fuel points system it's easy to effectively save a minimum of 14% on gift cards - including eBay gift cards - during their 4x fuel point promos (there's one going right now thru Jun 19), if in turn you paid for the SWA GC's on eBay with these eBay gift cards your total savings would be in the ~25% range.