Subliminal messaging is used by companies to sell their products and to make them money. Studies have proven it is very effective and as long as corporations are making money, they don't care if they are tricking people into buying their products.
So that you will want to buy their products as opposed to their competition's. They make you feel you need their product.
So that we become zombies whose only purpose is to buy the product :(
but i thought it was illigal?