One key thing to note is that the Merit team cannot force anyone to use invites they own in any particular way. We cannot censor how people decide to use them. When you get an invite, from mining, or waiting, getting one as a gift, or trading for one, it's yours and you can do with it as you please.

With POG2, we tried to create a more fair distribution of new invites. Since PoG2 release about 9k+ invites were generated and 7k+ wallets were created and there are more than 90k invites out there atm since launch. Some think using the market (trading invites) is an appropriate way to distribute them to those that value them. The merit team can't stop them from doing that because Merit is a decentralized system.
Again, unlike a centralized system, nobody can take invites away from someone and give them to another.