Never heard of Rocky Grass Festival but I suppose you would see a lot of things at a festival that aren’t part and parcel to the community it’s in. We get over 1.5 million visitors each year from all over the world for example. Well, we did but having the three most used routes in and out wiped out might slow that down.
http://www.bluegrass.com/rockygrass/
“The historic quarry town of Lyons is just 15 miles north of Boulder in the foothills of the Rocky Mountains.”