Yes, I know people "ignore low balls". But why? Thats the point of the discussion
It shows an utter lack of respect toward the seller. You aren't Best Buy, you are just a seller trying to represent what you have to offer transparently at a fair price. It makes the entire transaction reek when someone starts with a lowball. It also shows that they are either dumb, disrespectful, or just sleezy. You also risk getting poor feedback on the transaction.