If the prices are close, then buying direct makes more sense. The thing is, the off dvc use of points (using them for hotels, cruises etc) are a horrible use of points value wise. If we don't want to go to Disney that year, we rent our points out and spend the cash on a different vacation. Much better return than trying to swap for something else, which I couldn't do anyway since I've only had my points a few years and am not grandfathered in. I
am grandfathered in for the discounts though. Still . . . the discounts aren't that awesome, there are always other discounts that are close in value, and there is no guaranty that Disney will continue those. All I am guaranteed is a room and that's all I paid for.
I have owned at BWV, VGC, and SSR. I sold my SSR points last year, as we just had too many points for a family that is older and doesn't want to go every year. If I'd bought direct, that would have cost me a lot. Buying second hand meant I bought my points for about $80pp (loaded contract) and sold for $82 (stripped contract). The current rate for SSR is $151, which means as soon as you buy SSR points direct from Disney, your points will be worth a lot less--just over half-- what you would pay for them second hand.
This is magnified with other non-Disney timeshares, so if you buy from Hilton, be very careful to see what those points are worth on the second hand market.
I agree somewhat about the points eventually expiring. We will be selling our BWV points in a year or two to avoid dealing with that issue. Our VGC points are keepers. I'll be dead in 2060, and there is no place at
Disneyland quite as nice as a 2BR at the Grand Californian.