The people hiding their checkmark are not paying for the checkmark. They’re primarily paying to remove the restrictions Musk has thrown on free accounts. More ads, buried posts and replies, etc.
These folks are embarrassed about supporting Musk, but they’re still addicted to their old Twitter habit. They’re the addict who is sneaking drinks in the garage.
Not just that -- Twitter started automatically granting the blue check to any account followed by a certain number of accounts with the check. These people never paid but are being labeled as if they did.
The blue checkmark became a bad symbole so twitter started to give out blue checkmarks for notable people for free to increase the value of the blue checkmark.
However, the people started to hide the unwillingly gotten checkmark.