Hotel Room Prices

According to a show I saw recently on CNBC (www.cnbe.com,) hotel room prices can vary enormously depending on when you book and who you are. And that is for basically the same room, on different floors.
In an examination of Marriott Hotels (www.marriott.com,) the show revealed that on a recent day at the Marriott in New Orleans, LA, guests payed anything from $109 to $319 for the same basic room. Marriott caters to groups and business travellers, who may get special rates for frequent visits. For individauls, a hotel executive said the cheapest night is usually Sunday, leaving Monday.
Don't expect to be able to walk into a Marriott, even during slow periods, and get a price reduction on the spot, at least not in the U.S. I wonder whether this applies ascross the chain, which has a lot of nice properties in the Middle East, where bargaining is more acceptable.
And even if a Marriott is sold out, someone who is a very frequent guest may still be able to get a room there when you can't.
The program also emphasized that Marriott keeps track of every guest, and how much he or she spends in addition to the room cost. If you ever wondered what happened to the old fashioned hotel lobby where you could just sit around unbothered, the intorduction of lobby bars with wait staff is one way to maximize revenue on otherwise wasted space.
So if you manage to score a low room price and don't buy anything else at the hotel, when you go to make another reservation will you suddenly find the place is sold out, I wonder?