The intention behind this is clear to a native American English speaker, although it is obviously not appropriate OSM tagging. To an American, a concession stand is a counter which sells fast food to be consumed within a larger venue such as a sports stadium.  This park's website in fact describes it as such.

https://www.ncparks.gov/park-features/lake-james-state-park-paddys-creek-access

I've replaced this with amenity=fast_food at the recommendation of this wiki page.

https://wiki.openstreetmap.org/wiki/Tag:amenity%3Dconcession_stand