It seems that any story/crime out of Calgary is related to the DG case.
So considering the location, the guy just found it after not cutting the grass for two months or like other lazy Calgarian's he doesn't have sod (it's an odd trend in cowtown to just leave a lawn as dirt). If a machine gun was used, a suppressor may have been added to reduce noise.
On a serious note, believe it or not, but Parkhill is not exactly a quiet community when MacLeod is in full rush. People in that area seem to get desensitized to backfiring cars and Harleys and the constant whirr of traffic that common noises that startle most of us are brushed off as a Macleod thing.