I'm surprised it wasn't at LANL, considering one of the shops in Los Alamos near the lab has this amazing hatch chile burrito that's under $8 and is 10/10 in terms of flavor.
There are such places near SNL too. More, because Albuquerque is much larger than Los Alamos.
e.g. Vick's Vittles, Tia Betty Blues, Golden Pride, and of course the old standby Grandma's K & I Diner which has been feeding nuclear engineers for 62 years.
I, too, as a former Los Alamos resident, immediately thought of Viola’s. I don’t have any idea how many hundreds of Christmas breakfast burritos I’ve enjoyed there. Haven’t been in years since my Dad retired from LANL and moved to ABQ.
For those who do find themselves bothered by this kind of thing, these projects are almost always a few layers deep on what they're actually researching. I would assume this is more fun demo with a potential economic application in large scale roasting but that the research value (and intern training value) are in the general research area of broad solar concentrator R&D. If you look at the publication history for the folks involved you'll see a lot of papers on molten salt solar concentrators (materials, plant design, physics of etc).
Sandia does a lot of really interesting and valuable research (across all the sites but NM and CA in particular).