Matt to answer your question simply it is this. At a LFS they are ultimately trying to make money. If you have only 2 fish in a 55 gallon tank you will lose money, and go out of business, so they do things to make it more profitable, and profitable rarely means benificial to the fish. Also you can do things for 2 weeks that would kill a fish if done for 2 years simply based on the fact that you arent doing it long enough to kill the fish. Many times the fish are stressed from the moving and transportation and are over stocked so aggression is limited, however take that fish home for 3 months and you will see a completely differant animal. Also LFS's usually get juvinile fish, and juvi fish are not as aggressive usually as adults so you can over stock htem with success, but if you let those same fish stay there for 6 months you would lose virtually all of them. Basicly it boils down to this... you can not do what the LFS does not unless you are turning the fish over every 2 weeks. And I have to say from experience... there is a huge amount of die off unfortunately, you just only see the tip of the ice berg, I can only imagine what it must be like for LFS that dont maintain their tanks

Never look to a LFS setup for pointers on how to keep your fish!