there isn't really any poser bands, its just the posers that make them poser bands...if that makes any sense..
Just because those bands (ex: good charlotte, simple plan, etc.) are pop rock and all sound the same doesn't mean they are copying everyone else. They have just probably been influenced by the same music. maybe they don't want to sound like metal, they just want to play music and write meaningful lyrics (hopefully)
posers listen to bands like simple plan, good charlotte, blink 182,etc..so they make the bands look like poser bands even though those bands probably didn't mean to sound like everyone else