I regularly hang out with a friend who lives in the area, and my bus stop is across the street from 99 Rideau St. and this McDonald's. It's approximately 2 blocks from Parliament Hill and right on the edge of the Byward Market, which is bar central. At 2am this was one of the places people went after the bars closed. So yeah, it could get rowdy. Even now that the place closes at 10 pm, it's still in an area with higher than usual crime, lots of homeless, and drug dealers.
I don't think anyone's going to miss the place. Except the baby raccoons, maybe.