It's a good point. I've done that too. Several times. (Fluff on my balls is my excuse.)

But whenever it has happened, and I've noticed, I've always sent a /msg to the monk I dis-serviced to acknowledge my error. I had to apologise to Aristotle 2 or 3 times over the period of a couple of months for exactly this reason.

Of course, you may not always realise, or revisit the thread to notice.