Just people being oblivious to other people around them. Everyone is guilty at some point, but some examples are much more egregious than others perhaps to the point of intention. Case in point, a group walking on a busy sidewalk (think St. John's Town Center) very slowly and doing so 3-5 people wide with people also walking the opposite direction making it aggravating at the least to get around them and past them if you are unfortunate enough to find yourself directly behind them.

Also, at grocery stores or any store with aisles and carts and someone parks their cart in the middle of the aisle while they look at something on the shelf and someone else comes up either in front of them or behind them but can't get around because their body is blocking half the aisle and their cart is effectively blocking the rest of the aisle and although they know you're there they make no immediate move to assist you in getting by them. Blood boils just thinking about it and I'm probably one of the calmest people you'd meet.

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