That reasoning only works in the short term. Yes, you might think that renting points will be cheaper, but that is only true right now. What about 20 years from now? We own at SSR, so our dues cost us $5.44 per point, and we have long passed the breakeven point on our initial purchase. So renting is anywhere from $10-15 per point. We could make money by renting out our points every year, but of course, we always use them.
With DVC you have to look at the long term monetary benefits - not the short term costs. Once you have saved enough in resort costs compared to your initial investment (about 5-6 trips if buying resale), then all you are paying is dues, and the savings just go up from there. Historically, the resort costs for rooms has gone up more than our dues, and I see no reason for that to slow down. In addition, people keep talking about a 30% discount, but who knows how long that might last? And they are only good for certain dates, so may not even fit with your travel schedule.
Our last DVC stay was for 8 days in a 1bdr at VGF. To pay cash for the room would have been over $7,000 without the extra taxes and such. Using our points, and calculating the $5.44 per point for us, it cost us just over $2,000 in dues cost to stay there. A savings of over $5,000 just on the resort. Much more than ANY discount that Disney is going to release. Oh, and if you found a good rate of $12 per point to rent, it would have cost you over $4,500 to rent the points. More than double my cost.
I am the first to admit that DVC is NOT for everyone. It works for us, and many others, but it has to fit your travel style.