Permabanned people are usually not kicked in the lobby, because people don't believe players saying "He's a troll! He's parmabanned, kick him!"
This behavior is correct, since people could lie about someone just to troll them.
However, there should be a way to confirm that players are permabanned.

So, my suggestion is that you make a list of permabanned players, with their SC2 name. This would give a way to confirm a player is permabanned, simply by linking the page on the website.

I think it would make games funner, since lots of games are stuck with 14 players just because of a permabanned guy who doesn't accept his fate and still joins lobbies...