If you purchase tix using points and do not have enough RR points in your account for an upcoming booking, it is better than buying points at the full price. This promo is available just in time for the next schedule extension, which is next week, so, it's timing is good for those who want to take advantage of the extended schedule, but are short on points. If I have a choice between cash bookings and points bookings, I will go with the points, when possible, due to the many advantages.
I will not purchase points, however, unless an immediate need is there.