Contrary to popular belief this usage is not lazy or indecent nor is it as recent as many of you seem to think. At least as far back as the time of the American Revolution pls or plz was used in place of please in correspondence , again after the introduction of the telegraph, and most recently with the advent of text messaging, and all for the same reason, cost. During the early days of our country both paper and ink were expensive, so there were accepted methods of abbreviation to cram as much information into a letter as possible pls (or plz) was one example of this. When sending telegrams you were charged by the word (as in typing every 5 characters not actual words) so once again pls was used (among many other shortcuts u for you and so on) to make the sending of a message as cost effective as possible. As for text messaging, when first introduced, you may recall, we were charged per message we sent, so cutting letters out of messages meant a single text could be sent instead of two. It became a habit that carried over onto the internet, even though the need for the abbreviation no long exists,,,,to be fair though I am fairly sure you type OK or okay instead of Orl Korrekt which is the widely accepted original phrase the abbreviation came from, so can you really cast stones?