Instacart allows you to order groceries from various chains, theydo the shopping, and deliver them to you.

In the case of Stater Bros. coupon code STATERBROS20 will get you $20 off and free delivery on your first-time order.

I ran into one of their shoppers at Stater Bros. recently, and was told that they charge the same in-store prices for the groceries.

The "small print":
Offer valid until 11/28/16 at 11:59 PM Pacific Time or while supplies last. Credit valid only for first time orders made through Instacart of $35 or more.
See additional terms: https://www.instacart.com/help/section/200758544#207605853
Available in these zip codes: 92612, 92617, 92625, 92626, 92627, 92660, 92661, 9s662, 92663, 92704, and 92707.

I haven't tried this yet