When we were trying to book a hotel, my partner clicked on the top link of a Google search, which was of course a sponsored link and took her to some completely off-brand intermediary whose website was designed to mimic the appearance of the hotel's. She completed the booking there before ever realizing it wasn't the hotel itself, and when I quoted the same stay directly with the hotel it wound up being some $100-$200 cheaper.

I had to have a lengthy phone call with their customer support and exchange a few emails before they finally agreed to refund us. I suppose we're lucky they even had a reachable customer service, but I was and remain infuriated by the conditions that created the situation in the first place.