Ashley and Mary-Kate Olsen
06/01/2011 AT 01:00 PM EDT
Just call them art appreciators! Mary-Kate
and Ashley Olsen
stepped out at a benefit for the '80s graffiti documentary Style Wars
at New York's 1920 Bunker Club, where they chatted with guests and watched people break-dancing at the bash, which was deejayed by Adam "Ad-Rock" Horowitz of the Beastie Boys. The starlets were surrounded by artwork – including work by James Franco
– all of which was up for auction. As for the event, it was "pretty low-key, but very cool," a guest tells us.