Why is inch/ft easier than cm/m? As long as we use base 10, it seems trivial that units that are based on it are easier to deal with. Don't you hate it when uni

Why is inch/ft easier than cm/m? As long as we use base 10, it seems trivial that units that are based on it are easier to deal with. Don't you hate it when unit prices for the same type of product, say coffee, are sometimes printed in dollar per pound, other times in cents per oz? Multiplying by 16 in your head isn't exactly trivial. Then with cooking there is teaspoon, tablespoon, ounce, cup, quart, gallon... The fact that there are 12 inches in a foot, but 16 oz in a pound is just madness.