Only having a front tow loop means one thing your willing to take help but not give back or help someone else because you care more about put a whole in your ski then helping.
Although I agree, I think you missed the purpose of this thread. Seems to me like Mcdog was asking "HOW to hook up a rear tow loop" and not "do I really need one". Same for me, I would like to have one but since I've only ridden on a lake, the necessity isn't as great and now I'm trying to figure out how I put one on since I cut the back of the tray to accomodate trim.
Both of us have and would lend someone a foot before we left someone sinking.