As KAWS, Brian Donnelly creates cartoon-colored reworkings of well-known pop culture characters rendered slightly askew through recurring motifs — cauliflower ears and XXs for eyes — that give the effect of a dream half-remembered. His popularity, based on the raft of toys, fashion collaborations and multimillion dollar auction results, hovers somewhere near the mesosphere.

That Mr. Donnelly, who got his start writing graffiti in his native Jersey City, has recently joined the American Museum of Folk Art’s board may sound incongruous for someone routinely designated (and euphemistically maligned) as a street artist. But in fact he collects the work of self-taught and outsider American artists. In an upstairs living space in his Williamsburg, Brooklyn, studio, paintings by Joe Coleman and Susan Te Kahurangi King share the wall with large-scale canvases by Peter Saul, while R. Crumb comic panels mix with sketchbooks from graffiti legends like Phase 2 and Dondi White.

By joining the folk art trustees, Mr. Donnelly traces a neat concentricity with a board predecessor and shaper of an art movement, Andy Warhol, who could often be found at the Chelsea Flea Market loading his Dodge convertible with Americana and folk pieces.

“When I think of how I collect, it isn’t that I’m trying to be a part of some group or collect some type of work,” he said in his second-floor aerie, as assistants quietly colored paintings downstairs. “I just like collecting. It’s led me to a place where some of the stuff I collect is self-taught. I can’t compartmentalize it. For me, I just think of people making stuff. I find a lot of the self-taught stuff is a nice rabbit hole to go down.”