PM Read Receipts

Is there any way to disable this feature? I know you can just hit cancel but it is a bit of a pain. Why would anyone need a read receipt anyway, for income tax purposes?

I think it is just incase the other person doesn't reply, so you know they've read it and not just deleted it by mistake.

I imagine if the reader knew that the sender knows that you have opened the email then you'd be more likely to get a reply?