Katie Holmes Takes Subway in New York City

Katie Holmes is not above hangin' with the plebs ... she sat scrunched Friday between 2 dudes on a super crowded New York City subway.

Kate was solo in Soho, shopping up up a storm ... and then she took the R train during rush hour up to her swanky pad on the Upper West Side of the Big Apple.

And check this out ... she actually chilled to the point where she caught some ZZZ's during the ride.