Gee, I guess I hope that members would be a bit more aware/less dense than cash paying guests and realize that taking or breaking things in their villa just costs all members more in annual dues.
For precisely this reason (that breakage, loss, extra maintenance, housekeeping, etc. costs everyone more in annual dues), we take care of our villa at least as well, if not better than our own home. Well, that, and the fact that we realize we share
DVC resorts with other members and guests, so it's also common courtesy.
Yes, that's right - courtesy. Call me crazy, but when a bunch of sand ended up on our balcony floor at BCV (I was shaking the sand off our bathing suits after SAB) I swept it up. We also run the vacuum as required, clean the counters, turn off unused lights, make sure water is turned off completely, turn the A/C temp up when we are leaving the room...lots of little things that don't take very much effort or time. If something breaks, or we notice something wrong, we either fix it (if that's possible) or we call maintenance to fix it, so the next guest doesn't have to deal with it.

If everyone did this, everyone would benefit from lowered operating, mousekeeping and maintenance costs. Even as I'm writing that last sentence, I fully realize that it's unrealistic to expect everyone would actually do all this, but I'm sure YKWIM.
I have no proof, and I *know* many people claim otherwise, but I can't help feeling suspicious that a larger proportion of the non-members who do cash stay at DVC resorts (than members who stay on points or cash) have the attitude 'Who cares about that tear in the pillow, spill on the carpet, light that doesn't work, filthy mess in the bathroom, or the rack that just fell apart in the dishwasher.' I suggest that their thoughts when something happens is to justify leaving with a 'We'll never be back here...we paid for this villa. We're just getting our money's worth" or 'It's not my job to take care of it.'