Yeah, that's intentional. The spacing in between the sets of 0.1" header is due to the difference in the grid spacings between the header and the DB-19 female port. The middle pin in each strip of 5 is dead-center on the D-SUB 2.77 mm grid, then its neighbors are slightly off. Then the pattern repeats in the next strip of 5, so there's a little gap. If all 9 or 10 pins in the same row of the PCB were evenly spaced, then header won't fit into the D-SUB port.