They are a pop punk band. Real punk is a lot rougher.

okay, show me the book of rules for punk rock
labeling is exactly what punk is against anyway

http://en.wikipedia.org/wiki/Punk_rock
First read the main article to get a grasp on the history of the genre and associated movement then go deeper into each subgenre.
http://en.wikipedia.org/wiki/Punk_rock_subgenres

music is music for a reason
you don't need a backstory
even a band
just music



the problem with anything pop is that it isn't music, it's a product.
nofx isn't a product




go kill yourself

Your definition of pop is off. When something independent of a major label is described as "pop" it means that it is generally cleaner and more melodic. Twee pop, noise pop, dream pop, etc, aren't "products" either.

Also, calm the fuck down.

Edit: Also most pop punk is a product. It's made to be sold to angsty teenagers. Green Day is a great example of this.

Edit 2: Just because something is a product doesn't make it unenjoyable.

GREEN DAY IS NOTHING LIKE NOFX I HOPE YOU DIE IN A FIRE

U mad bro?
Y u so mad?