Amazon has a promotion for Get 5 For The Price of 3 on Pet Treats / Pet Toys with the discount shown at the checkout screen. Shipping is free for Prime members, otherwise on $25+ orders. Also stacks with S&S discounts / coupons. 

The pictured 6-count Scott Pet Pork Chomps Meaty Skewers is $6.99. Add 5 to cart for $35 - $14 multibuy discount = $21 ($4.20 per bag).