i think it's just part of our times:the customer is king, no matter what. I learned that long ago in retail - you won't believe what people bring back after one year, and then get into your face when you're not happy about it. It's also an American phenomenon, more so than what I have observed in lots of European countries I am familiar with.
About the free cancellation so heavily advertised now by Airbnb: perhaps it is less the fact of getting the service fee back 3 x a year, I think the increase is largely due to Airbnb tossing out the idea of refund in the first place. It helps them pull even with what hotels do, that is the idea...
Actually, it's not all bad for us hosts: we used to complain about not wanting to cancel, trying to get guests to do the cancelling, and then the standstill who will absorb the Airbnb service fees. So now it's much easier to get guests to do the cancelling if we need them to, so we don't get saddled with penalties. That is one if the giid things in there for us hosts