I totally understand where you're coming from with that. I for one am all about a name change. The big thing is coaxing my band members into it.
Just tell them it sounds like the typical garage brutal deathmetalxcorexindustrial band. They need to think of something more metal like Fetuspuncher or Cuntpunch... something that'll say "Hey, you know we're not just some creepy dressed kids, we have a purpose, to spread the blood of the innocent" You know? I'll give you a list of names actually never mind.
Try saying this to all of them at the same time, so you don't just get shot down by one of them: Have you guys ever Googled our name? I did and ALL of the results are for Mouth Sewn Shut because Google corrects the spelling. We're giving them all of our word of mouth advertising! We should come up with a name that gets us more exposure and doesn't cost us fans that end up at the other band's page. Then, if that doesn't work, throw in, "... and no one believes it's a play on words... they just think we're really bad spellers." I can't figure out what they could possibly argue about, since it's just an illiterate version of another band's name. I could maybe see them clinging to it if there was anything special, creative or original about it... but honestly, the name just screams laziness, to me at least. If they don't take you seriously, suggest these band names: Dear Hunter Drive Threw Whether Channel Pane Relief Yes or Know Reed Books Sewing Seeds Etc... Then, when they look at you like you're retarded, say, "Now you know how I feel." Then tell them to explain how any of those names are any different than the current name.