EC-CUBEでﾒﾙﾏｶﾞとってたら送料無料に

data/class/pages/shopping/LC_Page_Shopping_Confirm.phpの
102行目ぐらい。キャンペーンを参考に

//ﾒﾙﾏｶﾞとってたら無料
if($_SESSION['customer']['mailmaga_flg']==1 || $_SESSION['customer']['mailmaga_flg']==2){
$arrData['payment_total'] -= $arrData['deliv_fee'];
$arrData['deliv_fee'] = 0;
}