In my area (Ottawa) bottled water is usally used at gatherings by putting a case in the fridge or a cooler taking a bottle when you want some cold. When ice is available or the temperature doesn't matter much most people drink straight from the tap. Some people like to put tap water through a Brita filter before drinking it but I don't usually unless it tastes bad.
There are areas where the water is not as safe to drink, in remote areas like campgrounds and cottages water might have to be boiled before drinking and some places like native reserve are even worse off and I do not know what they have to to to get drinkable water. If you stick to the cities even the toilet water should be safe to drink