Print the new Hefty coupons.  Lots of stores have the trash bags on closeout and they are part of the Kroger mega sale.  Great time to stock up!
$1.00/1 Hefty® Tall Kitchen Trash Bags  
$1.00/1 Hefty® Large Black Trash Bags 

Hefty Trahs Bags, $3.40+
–$1.00/1 Hefty® Tall Kitchen Trash Bags  
–$1.00/1 Hefty® Large Black Trash Bags
As low as $2.40 after coupon.