The more I delve into these sites Booking and Expedia the more I start to realise how bad they are for consumers by creating a false narrative of 'available' options.
Another nasty nasty trick they have is to show you 'relatively' priced hotels in your search area. By this if you were to first arrive with a search of a $300/night hotel then they may only show you >$280/night hotels preconditioning the thought that that's the market. But if you had first searched a $50/night hotel (in say Ha Noi) then you results are in the range of venues $40-$200. A random search of hotels may not produce the full range of available hotels.
But how to list/identify all the actual hotels other than through those sites.
Even browsing Google Maps will show 1-2 hotels in an area but will be silent on other hotels even when zoomed in on the exact building, the hotel name will not appear. Search by name and Google knows and displays the hotel it just doesn't tell you unless you already know about it.
Even on a specific hotel, searching a hotel from outside a city may show 5 room rates, twin, double, deluxe blah blah. Searching that same hotel within its geographic area will often show additional room rates on the same rooms.
For an upcoming Asia trip over the next few weeks all my bookings are actually direct to the hotel sites. Maybe hotels are waking up also.