This is quite possibly not the case. Just like every other online aggregator (Uber, etc.), Booking.com spends a lot of money on advertising and incentives - meaning that on occasion, you will end up with an online price that is actually being *subsidized* by Booking.com. Not only are they not taking a cut on a particular booking, but the hotel may be getting more money than the customer is being charged - all for the nebulous goal of Booking.com capturing market share and driving out the competition (including the possibility of just showing up at the front desk).

If this seems incredible to you and you feel that this cannot possibly happen in real life, here's only one recent and amusingly told tale of online businesses operating in that way: https://themargins.substack.com/p/do...izza-arbitrage

Or maybe Booking.com has pre-purchased a large block of room-nights at the start of the season, and are re-selling those wholesale reservations to you at a tiny markup.

I can think of a couple more legitimate reasons for the front desk not being able to match or beat an online price. One is that the hotel is actually being *well* managed, and the management knows the likelyhood of filling up the rooms, and at what rates; the room that is not being given to you at a low rate may be kept back for, say, someone from the nightclub next door looking for a hotel room at 2am, and willing to pay full price - and the manager knows that is likely to happen.

Or perhaps the hotel has only prepared a particular number of rooms for the day, and even if they might technically have a vacancy, filling it may require calling out extra housekeeping staff the next morning - worth it at the walk-in rate, but a net loss at a discount rate.

Or perhaps - and I think this may be quite likely - the management has expressly forbidden the front desk from offering anything less than the desk price to walk-ins after a few too many of those cases ended up with the cash payment never quite making it into the hotel's books.