Yes, the Irish Brigade gift shop vacinity would be a good guess as to where the photographer is standing. My only guess as to why the people are standing in the street is that the picture was taken as the troops where being lined up for the parade. The things I'm certain on are:
The troops are on the Baltimore Pike, facing the camera, the house on our left in the photo behing the flagpole is the Farnsworth House. So that would mean the picture is taken in the direction of the town square which would mean the cemetery is behind the photographer.
I have no idea why the people are looking toward our left, maybe someone fell in the
mud.