Oh, I waaay prefer the artwork. In fact, had it been photos, I probably would have passed on the game. I suppose the license deal could have excluded stills from the movies, but for some reason I doubt it. If they have the license to reproduce the images with original artwork, then they probably have the license to use those images as well...
If they hadn't used artwork, they would've found themselves limited as Decipher once did. Decipher made the Star Wars CCG many moons ago, and when it came time to do EU and other things not represented in the movies, you received cheap CGI and employees posing in Star Wars regalia.
They weren't horrifically bad per se, but they stuck out like a sore thumb when in play with other cards that were purely movie stills.
With this approach, they are not limited to what types of cards they can design, or what sort of scenes they can depict. Plus, the art so far is really, really good.
... they probably already have license to the images.
Why would they pay for them and then not use them? I'm not sure you understand how licensing works. There's not one standard contract that you sign, pay one standard fee, and then do whatever you want with the property. You negotiate point by point what you'll have access to and pay accordingly. A videogame that uses FMV cutscenes lifted directly from the film, character models in the exact likenesses of the actors, and songs from the original score is going to pay way more than a shoe company just slapping the logo on a sneaker.
Was looking around for a bigger version and found this:
Apparently, it was done by Ralph McQuarrie who, according to Wikipedia,
"...designed many of the film's characters, including Darth Vader, Chewbacca, R2-D2 and C-3PO and drew many concepts for the film's sets. It was McQuarrie who suggested that Vader wear breathing apparatus. McQuarrie's concept paintings, including such scenes as R2-D2 and C-3PO arriving on Tatooine, helped convince 20th Century Fox to fund Star Wars..."
McQuarrie help define what we know as Star Wars, at least visually. Probably the strongest visuals are his designs, though there were others to be sure. I really missed his influence on the 'prequels', and miss him in general. Fantastic artist.