Maybe similar to the (alleged) reason cakemixes require you to add an egg: it makes it feel more like you baked it yourself if you have to do more than just add

Maybe similar to the (alleged) reason cakemixes require you to add an egg: it makes it feel more like you baked it yourself if you have to do more than just add water and put it in the oven. Maybe users feel like they ‘touched up’ their photo if they tap the magic wand button.