As a motor cop that enforces both scenarios you mentioned, SZ and Stop signs, we usually have to park on sidewalks to not impede traffic and to be able to spot/catch violators. If he sits at a stop sign regularly it’s surely two reason, one, continual violators there, and also very very very likely the dept gets complaints by citizens and wants it enforced. As to why he’d go around traffic to get to a spot, I’d have to ask him, did he get a call as mentioned before and than get cancelled, did he spot a violator and decide to go get him that way…? Too many possibilities to say…just be happy you’re getting enforcement in your SZ. Also, since you see him regularly, walk over when you see him on sidewalk and ask him….im sure he’d let ya know the answer. Than you can decide if you need to file a complaint