I've grown up always staying at one place, but on our trip last year to Yellowstone, we couldn't decide between two fabulous places to stay. That's when I got the idea to split the stay between the two places. It worked out well, the pros being a new setting, getting that beginning-of-your-trip feeling, new amenities, etc. The con was that after only a few days we needed to pack up and check-in to the new place, which was a little disruptive. I think in the future I will stay at one place unless there is a specific reason for changing (I wouldn't change just for the fun of it). I realize it's not for everyone, but I do see the benefits switching. Who knows? I may try it at WDW at some point just because there are so many hotels I have never stayed at and would like to experience. We don't have kids and we travel light, so switching is probably a lot easier for us than some others.
I never even realized people did this as a regular thing, again we only got the idea for our trip out west last year.
-Laura