When my dog was still alive, he was on a strict schedule for his insulin. Now we just wait for the first person to leave and then we go. Since we only go to grandkids' birthday parties, we can only take so much screaming and screeching, so we rarely stay more than an hour and a half.
They are but at least you can hear the clip pity clop pity of their horses hoofs when there coming to bust you. Not all of Canada's Provence's are policed by RCMP some have Provincial police and or city police or a combination of all 3. If you want to learn about a horrible part of Canada's history Google - Inuit forced migration + RCMP - and - Inuit sled dog massacre + RCMP. I figure what makes it horrible is it happened in the 1950's and we were supposed to be a civilised Country back then. Cheers!
Most of the events I attend these days are family parties, so if I'm tired or bored or have had enough of the kids running around, I just say my goodbyes and take off.
I leave when I’m ready. I never stay long enough for the subtle and unsubtle hints. I have a strict bed time I stick to. Usually after a couple of hours in a social gathering I’ve had enough and I go. No one takes offense. Everyone knows how I am. When I’m hosting I openly tell my guests it’s time to go.