'Advertise' and 'bait and switch' are words which have specific commercial meanings. You know the words but you don't know the meanings. An advertisement is an invitation to make an offer. A car dealer can put signs on the cars in his showroom. If the lotboy mixes up a $10,000 sign with a $20,000 sign the dealer is no more obligated to sell the $20,000 car for $10,000 than he is to sell the $10,000 car for $20,000.
Bait and switch is a pattern of behavior which is designed to entice customers to purchase a substantively different item. The pattern is essential to the fraud.
A meeting of the minds is a requirement for a contract. An error on the part of a sales manager or clerk in loading rack rates onto Expedia does not enable some dullard to claim to have an enforceable contract at the erroneous price. In this case Expedia was blameless and Hilton has no obligation to honor the price. Hilton was more than accomodating in the offers that they made.
Nevertheless, an advertised price is an advertised price. The payment agreement was acceptable to both sides, until the "error" was recognized. Too bad.
Perhaps Hilton should hire competent people to load their rates.
Such is life. Hilton screwed up and should deal with their mistakes. That's what honorable men do. They don't whine and hide behind a "whoopsie" and then call the customer a fool due to their errors.
If that's the way you run your business, hopefully you'll go belly up before you shaft too many consumers.