go ask a car manufacturer why they have non loaded, and fully loaded cars, maybe that will answer your question.
ya subs are different than cars, but its the same concept.
fully loaded cars have features that some want, some need, some dont need, and dont want to pay for them.
if a certain company only offered fully loaded cars, they might not sell as much as someone who sells a basic car that is more affordable. which is why they offer fully loaded as an option, its not on every car.
just as fi doesnt make them handle more power, if that makes the price rise and people dont want the extra power handling ability. it would just steer people away because prices are up and nothing u can do to lower them
i would assume a top 10 person for giving advice would understand such a simple concept.