<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by JS:
Someone correct me if I'm wrong, but I believe one of the purposes of posting a rack rate is that if you wish to stay in your room without a reservation (e.g., you don't tell the front desk you're staying longer, or you do but all the rooms are already booked, etc.), the rack rate is the rate you will pay.</font>
My understanding is that in most jurisdictions the hotel cannot evict you from a room if you choose to extend your stay, as long as you are paying the rack rate. A $1,000/night rack rate allows for a de facto eviction.
But the story I was told by my seventh grade Civics teacher (generally a trustworthy source) was that the mandatory rack rate cards came around with civil rights legislation, to counter hotel owners who had been forced by legislation to take down the "No [insert minority group]" signs, and instead switched to quoting outrageous rates to "unwanted" customers. I'm not sure how well the rack rate cards worked to that end; maybe it was before hotel owners got "smart" and started calling those outrageous stay-away rates the rack rate.