Many North American Opuntias are fruit-bearing plants. Apart from not to be underestimated inconvenience of glochids, they are eatable and sweet, with pulp full of large seed. Back in time, for the native people of the deserts the cactus fruit harvest season was a blessed time of easy and abundant food.
Now days in cactus collection they still keep the great decorative value. Once ripe, berries stay bright and fresh for couple more months. Squirrels in my back yard quickly learned to leave them along.