I've not had it happen to me but I have heard of it happening.
I recently tried to contest a charge on my card I was told I had to have in writing what I was supposed to be getting before I agreed to pay vs what I am getting after paying. This was in regards to a promotion I was offered over the phone, non refundable. Should've stuck with my gut and told them to screw off unless they were willing to send me something in writing. Now I'm stuck with it.
This was through Holiday Inn's membership program (forget what it's called). Called to book a hotel. Was offered a "resort preview" at any of their 5 new resort locations for $250. If I sit through a presentation I get my $250 back so its free. Even though it sounded fishy on the phone I am a long time customer of Holiday Inn so I thought it was legit and figured I could deal with a 2 hour presentation harassing me to buy something. I agree to the promotion. This was in like April. So in May I pick a location (Smoky Mountains) and a date (early October). So about a week ago I start trying to plan this in a little more detail and review the confirmation letters and realize I am not staying in the resort, like I was told on the phone, I'm staying at a regular Holiday Inn 20 minutes away. The only thing indicating this in the information I used to pick the locations is that the address of the hotel is different than the address of the resort but since I was told it was at one of the resorts I never bothered to look up the addresses of the resorts and make sure they matched the addresses of the locations I got to pick from. I try to cancel and of course I can't without losing my $250, even though they lied to me. On top of that, they tell me if I miss the presentation, or am somehow disqualified, not only will I not get my $250 but I will be billed the full retail cost of my stay which will range anywhere from $300-1000.
Called my credit card company to see what my options were and that's when they told me I should've had it in writing first.
So, I got ripped off by an obvious scam and Holiday Inn will lose my business forever. Considering I generally stay with them about 5 days a month, almost every month, and would have for the rest of my career, I think they lost more money than ripping me off was worth but I guess they thought differently.
TL;DR: I'm an idiot that trusts big companies I deal with a lot and agree to their sketchy sounding promotions. Don't trust Holiday Inn.
Off topic: If visiting the Smoky Mountains in October am I likely to hit snow? Are there areas/attractions that I'd be better off taking my SUV to get to over my 944 coupe? Flights were too expensive for my liking so I'm going to drive.