Its not a myth. Its simply a case of supply and demand and well, economics in general.
If demand increases, and supply remains the same (you can't build hotels quickly) then prices will go up. They do go up.
To give you a simple example of this, I am booking hotels in Amsterdam for a technical conference in November and I am not finding any available rooms, and all room rates are almost double what I paid last year.
This was confusing for me so I called one of the hotels and they informed me that there are two other conferences and a concert going on during the event, which is why rooms rates are different as they only have the premium rooms left.
Even if you were to discount that as something that could be avoided, almost all hotels have at least these different types of rates:
- The walk-in rate (most expensive)
- The corporate rate
- The online rate (at their website)
- The online rate (at other sites/resellers/travel agents)
- The preferred rate for loyalty card members.
- The rate for rooms when booked as part of a business conference.
- Seasonal rates (based on travel seasons - ie, Christmas/New Years, etc.)
These are all different prices for the same room.
As a general rule prices go up when:
- There is more demand than supply (busy season, weekend, etc.)
- The later you reserve (last minute seats, walk-in bookings)
This applies to both airlines and hotels; and other similar hospitality/entertainment/travel industries like amusement parks, concerts, trains, buses etc.
So not booking a weekend but booking on the weekend compared to
booking during the week. If that is true it would actually be a very
interesting point to consider.
As a general rule it does not matter when you are booking - it matters when the actual booking is, relative to the current time.
So if you were to login on Christmas Day, to do a book for March 1st, you would actually get a cheaper rate than if you were login on April 15th and do a booking for March 1st.
For hotels specifically, it also matters what type of property it is.
You can easily observe this by booking at business hotels (or those that are near airports). These properties will have drastic price differences if you are booking on the weekend or during the week. A booking during the week (for example, checking on Monday checkout on Wednesday) is more expensive then checking in for the weekend - because they are busier on working days than weekends.
Compare it with a resort or family-focused property and you'll see for the same dates and the same class of room, completely different prices.
Online though, there are other things you have to watch out for.
There was a case some years ago from Orbitz that would change prices if you were browsing the site from Apple devices. This article from 2013 at USA Today highlights the details and includes evidence that Delta was doing similar tricks for the pricing search.
I am sure since then practices have become more complicated and there are variable number of points that go into pricing of fares for both flights and hotels (and then, of course when you combine the two with a package).