This might be a bit of a stupid question, but how do you leave the shop after selling everything?
On the 1st page of your catalogue there are 3 buttons for "Park", "Junkyard" and "Carnival". Hope that helps!
In case you plan to keep working on the game after the jam, this was also something that stumped me for a bit the first time I played :)
We are definitely going to work on it after! We have a tutorial written up that sadly didn't make it into the game.