In order for a player to know a game’s space, both in spatial terms and in terms of what actions are possible to make, they need to get intimate with it. The player has to go through the boring process of walking about in order to make a mental picture of the surroundings. If they don’t, they cannot possibly know what the realm of their possibilities are.
This is especially true for Gone Home, with its slow walking pace and ability to interact with most of the items in the house, even if many of them are completely irrelevant to the story. This intractability encourages the player to uncover and move as much as possible to try to find the complete story.