Petsmart & Their Workers?

I went to petsmart about a hour ago and just to test the woman working back there I asked her how many black skirt tetra could I keep in a 29 gallon tank. She told me as many as I want and then I asked how would they get along with zebra danio and she said that she didn't know. Has anyone else ever had anyone else like this at a petsmart that didn't know anything about fish?