Grumpy Greens location is important because Fortnite Season 2 brought with it loads of weekly challenges to work toward unlocking the faction choice for various agent skins. After completing a certain amount of challenges, you can choose between having the agent join Ghost or Shadow.
Here in Week 4, the new set of challenges is for TNTina, which features 10 challenges. One of the challenges is to visit Grumpy Greens, Mowdown, and Risky Reels.
You can find Mowdown north of the apple orchard in between Pleasant Park and Craggy Cliffs, while Risky Reels can be narrowed down to the circle of trees north of the Agency.
With that in mind, here's where Grumpy Greens is.
Grumpy Greens Fortnite Location: How to Complete the Week 4 Challenge
Grumpy Greens is located east of Pleasant Park, just to the right of it if you look at the map. Once you get to that spot, you'll see a group of shrubs shaped like a frown. This is the grumpy location.