People's situations, needs, and perceptions are different. i don't carry spare contacts because I wear glasses (my spare glasses are in my vehicle because I must wear glasses to drive legally).

I always carry a canteen when hiking but not whenrunning errands around town.

At one point in my life, when working in Canyon de Chelly (NE Arizona), my EDC included at a minimum sixty feet of 9mm climbing rope - for some projects this was upscaled to 600 feet of 11mm cord. But I always had the minimum....and there were times I was very glad I did.

EDC is a very individual thing...