Like I said, people have different expectations. You can also see when people are logged into Facebook because they are available to chat with. How would you react if they were logged in but you didn't have a read receipt? Or there was a receipt but they didn't respond?

Anyhow, this is all just proving the point. Read receipts introduce a piece of "evidence" that is bound to be misinterpreted. So I don't like them and they're yet another feature hostile to some customers in Facebook.