Think a lot of the better known ones either are not working, or people are maybe not wanting to advertise them too much possibly in case demand and prices increase accordingly?
Some of the better ones appear on say page 10 out of 20 of an AW search, so you see loads first that might look good in their photos, promise the world, yet don't deliver.
It's the same as most Romanians. They advertise, horny men decide to visit, have a bad experience and don't return. Next man comes along and keeps things ticking over. Repeat customers aren't a concern of theirs as there will be a steady supply. If not, name or location change.
The NE isn't much better. Take away one, or maybe two agencies, and that's most reviews gone.