I suspect these are mostly professional renters who have computer programs/algorithms to help secure the walks more easily.
Why would they do this? If I am a professional renter, I probably have a fair number of points. If I have a fair number of points, I don't need e.g. the Wine and Dine weekend, I just need
some dates at high-margin resorts, and if I don't get some particular dates, fine I will just get others. So I wouldn't need to walk them, I just need to book them.
That's not to say that there aren't automated mechanisms some people use for booking. I am sure there are. But a commercial renter would be more likely to use them just to book something when they have points available.
Instead, I suspect the increase in walking is just happening because more people know about it, they (rightly or wrongly) think they need to do it, and so they do---and that creates the impression that there are more times/units that need to be walked, which generates a self-reinforcing loop. I've certainly see this play out watching availability. There is a pretty clear pattern of walking---only the 11-month-to-the-day day is booked, and it keeps moving. Even some of those day-of days last a few hours after 8AM. So, definitely not a time when walking needed to happen.
I’m traveling in November and the only studios not being walked or already completely booked are OKW and Saratoga.
Those are still almost all in the home resort window. That's probably not things that are being walked, those are things that were probably booked by home resort points. Some of those may have been speculative rentals, but most are probably just owners using their points.