Okay, since you are casting doubt on my character let me put it another way, people DO NOT go looking to buy domains in bulk from other people.
They choose ONE domain and then go searching to see if other extensions are available. Much like making a pie, they find one specific base ingredient like beef and then build the recipe around that rather than grabbing everything in a bulk bag sitting in the supermarket aisle regardless of what it is. (And if you have ever had custard with beef you will know why they do not do that)
Someone does not wake up one morning and suddenly decide that they absolutely must have 100 domains on a theme which may or may not be completely random and which may or may not be remotely connected to what they do or what anyone in the world does.
If you think they do then I can only assume you are an idiot.
When people are exploring they are not looking for the whole bloody forest, they will be looking for one tiny part of it, be it a path or a trail or a colourful butterfly or flower. You do the same at the supermarket, you pick and choose what you want depending on your own specific tastes, it might be nice of the market to put the pasta with the mince and the tomatoes but it certainly is not practical. And they certainly will not expect you to buy everything in that section just because you bought one item. Though they may wish you had.
They put the beef with the meats, they put the mushrooms with the vegetables and the pasta with the flour or other pasta goods because they know that people have been hardwired over 65,000,000 years of evolution to look for the one specific thing they want. Our eyes have evolved to only pick up a 2% field of depth, to pick up any more would mean our brain gets overloaded and we turn into H.Simpson after 30 bottles of duff. It happens with everything we are searching for, we focus on our car keys and ignore the remote control stuffed down the back of the sofa.
See what I did there? I took your insult and upped the ante with actual psychological fact, isn't this fun? (And I didn't even use the laughing thing to lighten the mood of what I was saying once)
Here is a fun experiment, why don't you make this company, take everyones crap in bulk at the price they expect and see how long it takes you to go bankrupt when you tell your customers they have to buy everything in each lot? (That was me suggesting the business model does not work therefore no one does it)
If you want to list domains in bulk then simply use various forums.
I also looked at boxcar.com and considered it but even that would not work even though it is a great suggestion, you suggested you wanted to sell ALL of them in one go. Specifics Bob.
You have to be specific with what you are asking for on forums, don't you know that? Now, if you have a list of domains that you wish to list and have people pick and choose what they want is one thing, but your initial question was "Any companies people have used to sell all in bulk?"
Specifics, Bob ~ George Malley