I thought I had already posted this but as per the posts above. Its not like you are going to some isolated vacation spot that only has some little corner store to shop for food.
The area is a major metropolitan center with everything you would expect in your home town. Though there is one place you shouldn't shop at is Goodings in the Crossroads. I have heard its very expensive.
But anyway lets say it was 20% more for groceries. Think of it this way, what is your alternative? Eating every meal in a restaurant which would cost a lot more.