As long as the LFS isn't saying that a fish will be fine in a tank that its not going to be fine in then there is no misleading.
I find my LFS (big box store) has lots of knowledgable staff, and will be more then willing to give there opinion on how fish will interact or do in a tank or find someone that will have a better answer.
But if they are not asked they do not ask. And why should they? They are not the fish tank police, should you have to go to a store with a water sample the start date of your tank, its exact contents, the last time it had a problem, what that problem was, etc etc etc?
Nope, they assume the customer knows what they are buying and what they have if they do not ask questions.
I know the assume saying, but in this case the only *** is the customer.
Just today when I was buying a tube anemone there was a couple in there buying a lion fish, a queen angle and a manderin goby, they asked a couple questions, like how big, what they eat and if these fish will do ok with a couple of clowns that are territorial about their anemone, sounds like they know what they are doing. As the guy was catching the fish he asked me about my tank, I mentioned I wanted the tube but my tank has only been up for 5 months and I am crossing my fingers. His answer, "it'll be fine, we set up our 35 gallon tall last sunday and got our anemone wednesday and its doing great, better then it looked here in the store". (its friday, so not even a week).
As soon as the staff grabbing the fish heard he said (before I could) "everything in your tank is going to die, and if for some maricle they dont everything will be far too large for your tank"
Customer said the fish will fine and he will make it work. He paid just before I did, 340 and change after the red brittle star and some other inverts.
I don't know why I shared that but its long and I already typed it. And its kind of on topic.