From the wilderness wallpaper at Granny’s Diner, Mushrooms in Archie’s office, and much more there are many hints to remind you where the cursed inhabitants came from, but we see more in the “HAt Trick” episode:

See the branches arranged along the left wall?

See the tree filled wallpaper?

See the vine-like design in this wallpaper?

See the silver tree like rack in the back corner next to the guitar?

See the grass-like shag carpet? See the flower printed drapes? Almost the entire decor has clue after clue of Fairy Tale Land. With all the reminders and his heart breaking for his child, no wonder the Hatter went mad trying to get back.

Did you notice any other clues to FTL?