I've recently put a couple of players on the TL that didn't sell and I've seen my fan survey rating in that area drop from four balls to one and a half.
That is true, however, I don't think it impacts the attendance that much. There might be a slight drop, but that drop is going to occur even if you put the player up for 1k. The difference is that if you list the player at 1k then he might sell for 1.2 million and you might be disappointed because you didn't get more for him.