The irc is how it gets IP addresses for nodes, and it does this by looking at join messages in the IRC channel it's in. If you don't create a new channel then you will get peers from whatever other coin is in that channel. That's bad. You should have your own channel for your coin. Otherwise it will take forever for any new users of your coin to find peers, because all of the IP addresses it will try from IRC are not using your coin but someone else's.