MenachemAs for hosting lobbies, Stadium has done a few things that TF2C doesn't, like saving your server's address
I'm not sure if this is the reason why TF2C doesn't save server addresses but I think it's because they don't want people to spam opening up new lobbies. It's an additional barrier that they've placed to prevent people from opening new lobbies immediately upon seeing that there's no lobby open that they're interested in. Too many open lobbies means that they all get filled much slower.