When I was buying my two VT girls Mimosa and Electra, the sales lady asked me if they were going in with a male betta "because everyone who knows about bettas knows that they'll be much MUCH happier!" "Now why would I ever do that? They'll get their own tanks!" I said back to her (perhaps came off as a little snobby, but oh well :/). And she looked at me like I had three heads and was painted green.
And just recently a salesperson asked me if bettas can live in brackish .... O_o I was like ... "noooooo ....."