Yep. All kinds of private deals. It's not illegal, nor against ICANNT rules (if they had any)
It does bother me about the shift from the public and individual domainers to the deep pockets, and the whole secrecy thing. Nobody used the word conspiracy here, but there is definately a big lack of transparency in this business. You have to ask yourself why that is?
What I've seen is that a lot of the deep pocket guys came from spam, phishing, and blatant TM cybersquating, and they are using that "dirty money" to buy registrars etc. How soon will it be before there are NO drops going to domainers? Better put on your developer hats and get ready for a domain price increase from these guys and the registries.
I disagree with your observation.
Initially it was domainers like Yun Ye et al running scripts to catch the drops. Pool+Snap+Namewinner muscled out the individuals and opened the market up to everyone who'd pay. The original players were forced to pay higher prices going through the public services for a while, but in the past year or two they've caught on and set up their own registrars ($20-30k up front + $6/name sure beats $1000's/name at auction).
Maybe some of them have portfolios with tm infringements, but that really has nothing to do with it.
The "lack of transparency" is because the people who got here first were smart enough to stay quiet and maintain some competitive advantage. The rest of us latecomers are left to jealously drool over their portfolios.
If you want to criticize someone, look at Enom and Dotster. They have gone from pure registrars, to public drop catchers, to two of the top portfolio owners. The registrars have become domainers and built their portfolios using the money we spent buying the drops they caught. And even that is fully within their right.