I couldn't ever make this my only grocery stop because it doesn't have the variety that I need from a grocery store, but man does it have some delicious food!
Number one is the produce. Loads of fresh produce, and samples for you to taste before you buy. ....or you know, snack your way around the store...
They also have a pretty amazing cheese section. Mostly Wisconsin cheeses with a few other specialty cheeses as well. I am not a cheese expert and have gone there looking for something kind of specific and was able to have someone knowledgeable enough to point me towards what I was looking for and telling me why certain kinds would or wouldn't work for what I wanted them for.
They also have a pretty amazing beer section. Lots of unique local selections, and also something that they seem to be pretty knowledgeable about when questions come up.
There are other things they sell as well, snacks, meats, seafood, and some other random frozen items. You can find quite a bit of Brennans branded local items, as well as a few other local brands.
I don't get here often because it isn't a one stop grocery shop, but when I do go I wonder why I don't come more often because I always find such great things!