I do a monthly menu plan and grocery shop once a month. There are some days left blank becasue hubby likes to bbq. It is just us but he is shift work and I work till 5. 45 min drive home not always in the mood to cook so a plan helps and I do some meals on the weekends and freeze to have ready to just take out for the really bad days.
Hubby has been grocery shopping with me for several years now. At first he did cause more expense but has jumped on the coupon band wagon and also makes sure the reusable grocery bags are in the car.