I'm not gonna say some of these shops don't over charge, the key like has been said is shopping around. I'm a believer in you get what you pay for to some extent, but I also believe you can get fantastic products for growing that aren't geared towards cannabis growers cheaper. I also tend to subscribe to the less is more belief, I've experimented with several different nutrient programs, and have always had good results no matter what brand it was. This is one of my favorites by far and what I plan on going back to in the near future
http://www.texashydroponics.com/shop/product.php?productid=2204. Its a fantastic nutrient that isn't geared towards cannabis and costs about half of what many others do( 8 cents per mixed gallon of nutes).
So anyway where I'm going with this is the OP obviously has some anger issues, and a hard time expressing himself cus he keeps repeating the same posts over and over. You can deffinitely grow some weed with lights from lowes, and some dirt from the back yard, and a fish and fruit and no nutes and so on and so forth. But the point is...you WILL grow much better cannabis if you invest some time and money into maximizing the environmental conditions, period. You will yield better and you should end up with a better quality product without a doubt. You keep saying that you shouldn't have too spend 200 to put a seed in the dirt, and you don't, but if you want dense, heavy, tasty colas, not just some buds then you will spend it.