Beware of tricks to get you to open emails as well. Like "Congratulations on your sale" or a variation, you open it to find you really didn't make a sale. They want to sell you something to help you make more sales. I unsubscribe if you trick me into opening a message. Fool me once and I can't trust you. Any kind of deception is not acceptable. I have stopped putting up with it. You can make your own calls on this touchy subject. Keep in mind, the potential buyer always is the final judge on these matters and the more crap that is tolerated, the more crap that's on the way.