We travel very little, so, we were not aware of this -- anyone who travels a good bit may know about it.
Be very careful when you book online because it could cost you big time.
Try this: Assume you want to book a room in, say, a Holiday Inn Express in Little Rock, Arkansas. Google "Holiday Inn Express Little Rock" then look VERY CAREFULLY at the URLs on the results. You will see all sorts of links that look like they are to the hotel, or to the Holiday Inn booking site, but instead these URLs take you to a carefully-concealed thrid-party booking site -- you will NOT be booking through HI or the hotel.
Why is this important? This is what happened to us. I booked, unwittingly, through a third-party site. 36 hours before check-in, we had to cancel. I called the motel and cancelled. Next month my credit card showed the full charge for the stay. I called the motel, talked with the manager who explained things to me.
It seems that third-party sites use applications that constantly ping reservation sites checking their prices. If you made your reservation through one of these sites, and they find a price cheaper than the price at which you reserved your room, they will cancel then rebook you at the cheaper rate, often at the last minute -- you never know about this. Hotels/motels retaliated by placing limits on cancellations -- that is, I cancelled 36 hours before check-in, but, the motel now required cancellations to be 48 hours before because they were losing so much to the third-party booking agencies.
The manager who explained this too me also said they are placing surcharges on rooms booked through third-party sites -- not much but it adds to your bill and you may not even notice it.
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