I've seen game-worn jerseys with dirt on them in the Amazin' Memorabilia store at Citi Field.
Best photo I can provide, however, is this one from the 2013 MLB All-Star Fanfest in New York. Among the items available for purchase in the Authenticated Game-Used Memorabilia section of the MLB Clubhouse Store was a David Wright jersey with plenty of dirt on it. Didn't note the price or the MLB Authentication hologram number so I can't provide any further details...
