I think part of that comes down to two reasons. Railfan photographers focused on the trains arriving and departing the old terminal and the fact that it was demolished so early as the Erie moved their passenger operations to Hoboken just before they merged with the Lackawanna Railroad. Finding photos of the interiors of both Exchange Place Terminal (Pennsylvania Railroad) and Weehawken Terminal (New York Central Railroad) is also tricky, as they both were torn down around the same time as Pavonia.