Miracle Grow is this irritating, un-itchable spiky burr of a peeve for me. Their products have taken over the shelves in most stores, so you have very little choice in commercial potting soils or fertilizers any more. And while their products are complete, they're all high nitrogen. I don't know how many times I get asked "I have a <insert plant of your choice> and it's really healthy looking, but it doesn't bloom". Get 'em off the Miracle Grow and the plant will bloom, and, as a bonus, any problems with aphids go away.
And the sheer cold genius of the marketing...getting consumers to use a product that makes the plant look lush, but does nothing for the soil, so when they run out of Miracle Grow, they have to go and buy more. ARGH!
Miracle Grow isn't evil, it's a simple way to boost a poor grower or to quickly correct a specific deficiency problem; but the over-marketing sure makes it seem evil sometimes.