in case you want to change some of the wppizza custom post type arguments (for example, turning off comments which are by default enabled and/or adding tags which are by default disabled) try something like the following.

add_filter('wppizza_cpt_args','my_wppizza_cpt_arguments');
function my_wppizza_cpt_arguments($args){
/**disable comments**/
$supp=array_flip($args['supports']);
$cid=$supp['comments'];
unset($args['supports'][$cid]);
/**disable featured images**/
$supp=array_flip($args['supports']);
$cid=$supp['thumbnail'];
unset($args['supports'][$cid]);
/**enable tags**/
$args['taxonomies']=array('post_tag');
return $args;
}