The only reason that I mute anybody is to keep them quiet if they are doing something chat-related. If they are not doing it anymore (due to the mute), I don't ban them. God if I banned everyone who caps spammed, there would be nobody at the server. If the guy's mute runs out, he evades it, or he gets unmuted and continues, then I will ban them*
*At Tezuni's, being a moderator, the bans only last for 10 minutes. About 30% of the time, a person I ban will come back when their time is up, so sometimes I just have to keep banning until an admin comes around.